BERKELEY 

LIBRARY 


i'vi'r^iir^M 

MINERALOGY-, 


INCI  '-DINO 


OBSERVATIONS  ON  MINES,  ROCKS, 

REDUCTION  OF  ORES, 

• 

AND    THE 

APPLICATIONS  OF  THE  SCIENCE  TO  THE  ARTS. 

WITH  260  ILLUSTRATIONS. 

DESIGNED  FOR  THE  USE  OF  SCHOOLS  AND  COLLEGES. 


BY  JAMES  D.  DANA,  A.  M., 

Member  of  the  Soc.  Cms.  Nat.  Cur.  of  Mosc6w.  the  Soc.  Philomathique  of  Pari«, 

the  American  Academy  of  Arts  and  Sciences  at  Boston,  etc. ; 

Author  of  "  A  System  of  Mineralogy." 


THIRD    EDITION. 

NEW  HAVEN : 

PUBLISHED   BY  DURRIE   &   PECK, 
PHILADELPHIA  :  HORACE  C.  PECK. 

1851. 


\>t>S>         v» 

>5/ 


•   t-'a  *       *  *   «  **  *      i 

sV     .  v*  :Sr!X3! 


Entered  according  to  Act  of  Congress,  in  the  year  1848,  by 

DURRIE   &  PECK 
in  the  Clerk's  Office  of  the  District  Court  of  Connecticut 


Stereotyped  by 

J.    H.    BENHAM, 

New  Haven,  Ct 


iff 


EARTH 

PREFACE.  ?f'BNC 

LIBRARY 


IN  the  preparation  of  this  Manual,  the  author  has  endeavored  to  meet 
a  demand  often  urged,  by  making  it,  as  far  as  possible,  practical  and 
American  in  character. 

Prominence  has  been  given  to  the  more  common  species,  while  others 
are  but  briefly  noticed  in  a  smaller  type,  or  are  mentioned  only  by  name. 
The  uses  of  minerals  and  their  modes  of  application  in  the  arts  have 
been  especially  dwelt  upon.  The  value  of  ores  in  mining,  their  modes 
of  reduction,  the  yield  of  mines  in  different  countries,  and  the  various 
applications  of  the  metals,  have  been  described  as  minutely  as  was  con- 
sistent with  the  extent  of  the  work.  The  various  rocks  are  in  like 
manner  included. 

At  the  same  time,  the  subject  has  been  presented  with  all  the  strict- 
ness of  a  scientific  system.  The  classification  adopted  throws  together 
ores  of  the  same  metals,  and  associates  the  earthy  species  as  far  as 
possible  in  natural  groups.  This  order  is  preferred  by  very  many 
teachers  of  the  science,  and  has  advantages  which  for  many  purposes 
counterbalance  those  of  a  more  perfectly  natural  system.  The  account 
of  the  ores  of  each  metal  is  preceded  by  a  brief  statement  of  their 
distinctive  characters  ;  and  after  the  descriptions,  there  follow  general 
remarks  on  mines,  metallurgical  processes,  and  other  useful  information. 

As  the  rarer  mineral  species  are  not  altogether  excluded,  but  are 
briefly  mentioned  each  in  its  proper  place  in  the  system,  the  student, 
should  he  meet  with  them,  will  be  guided  by  the  Manual  to  some  knowl- 
edge of  their  general  characters,  and  aided  in  arranging  them  in  his 
cabinet. 


IV  PREFACE. 

The  list  of  American  localities  appended  to  the  work,  the  descriptions 
of  mineralogical  implements,  and  the  notice  of  foreign  weights,  mea- 
sures and  coins,  will  be  found  convenient  to  the  student. 

The  author  must  refer  to  his  larger  work  for  more  minute  information 
on  the  localities  of  minerals  and  the  associations  of  species — for  full  lists 
of  synonyms — for  tables  for  the  determination  of  minerals — a  more 
complete  account  of  crystallography  and  its  details — chemical  formulas 
of  species,  and  more  numerous  analyses,  with  their  authorities — and  a 
list  of  mineralogical  works  and  journals.  He  has  there  expressed  his 
indebtedness  to  the  various  Geological  Reports  of  the  different  States, 
and  also  to  the  scientific  journals  of  the  country,  for  information  on 
American  minerals.  In  addition  to  these  acknowledgments,  he  would 
mention  his  obligations  to  Prof.  C.  B.  ADAMS,  of  Amherst,  Mass.,  and 
Prof.  M.  TUOMEY,  of  Alabama,  authors  of  Reports,  the  former  on  the 
Geology  of  Vermont,  and  the  latter  on  that  of  South  Carolina.  Aid 
has  been  received  in  various  ways  from  Prof.  B.  SILLIMAN,  Jr.,  and 
much  valuable  information  from  Mr.  A.  A.  HAYES  of  Lowel,  Mass., 
H.  KING  of  St.  Louis,  and  S.  S.  HALDEMAN  of  Columbia,  Pennsylvania. 
Ure's  Dictionary  of  Arts,  Manufactures,  and  Mines,  has  been  a  work 
of  frequent  reference,  and  the  figures  of  a  zinc  furnace  are  from  that 
volume. 


TABLE   OF  CONTENTS. 


CHAP.  I. — GENERAL  CHARACTERISTICS  OF  MINERALS, 


13 


CHAP.  II. — CRYSTALLOGRAPHY:  OR  THE  STRUCTURE  OF  MINERALS,       19 
Fundamental  forms  of  crystals,          .  . 

Cleavage,  . 

Secondary  forms,      .... 
Compound  crystals,  .  .  .* .  • 

Dimorphism,  .  .  •  • 

Irregularities  of  crystals,  .  • 

Measuring  angles  of  crystals,  '». .      .• 

Massive  minerals,     .... 

Columnar  structure,       .  .  . 

Lamellar  and  granular  structure,  . 

Pseudomorphous  crystals.      .  .  . 

CHAP.  III. — PHYSICAL  PROPERTIES  OF  MINERALS. 
Luster,  .  .  .  . 

Color,  ..... 

Diaphaneity, — Refraction,  and  Polarization, 
Phosphorescence,      .  ".  .  . 

Electricity  and  Magnetism,  .  >    •        . 

Specific  gravity,        .  .  i    *        . 

Hardness,     .  .  .  •-   •         • 

State  of  aggregation — Fracture,        .  , 

Taste — Odor.  .... 

CHAP.  IV. — CHEMICAL  PROPERTIES  OF  MINERALS, 
Action  of  acids,  .... 
Blowpipe,  .  .  «,  .  ' 

CHAP.  V. — CLASSIFICATION  OF  MINERALS,  • 

CHAP.  VI. — DESCRIPTION  OF  MINERALS,   .  -, 

1.  Gases,      . 

2.  Water,     . 

3.  Carbon  and  compounds  of  carbon, 

4.  Sulphur,   . 

5.  Haloid  minerals, 

1.  Ammonia, 

2.  Polassa, 

3.  Soda, 

4.  Baryta, 

5.  Strontia, 

6.  Lime, 

7.  Magnesia, 

8.  Alumina, 


vi 


CONTENTS. 


6.  Earthy  minerals,  (silicates  or  aluminates,) 

1.  Silica,        ,   ,          -  ,. 

2.  Lime, 

3.  Magnesia,     . 

1.  Hydrous  silicates,      ^  ^    , 

2.  Anhydrous  silicates, 

4.  Alumina,       .  'V 

^,    j%v       1.  Uncombined,     .        '  " . 

2.  Combined,  as  aluminates, 

3.  Hydrous  combinations  with  silica, 

4.  Anhydrous  combinations  with  silica, 

5.  Combinations  of  a  silicate  and  fluprid, 

6.  Combination  of  a  silicate  and  sulphate, 

7.  Silicate  with  a  chlorid. 

5.  Glucina. 

6.  Zirconia. 

7.  Thoria. 

7.  Metallic  ores. 

1.  Easily  oxydizable  metals,      .  f.':, 

1,  2.  Cerium  and  Yttrium,  . 

3.  Uranium,         .  .  . 

4.  Iron,    .  .  .         /•»-'.• 

5.  Manganese,     . 

6.  7.  Chromium,  Nickel,  .  . 

8.  Cobalt, 

9.  Zinc,   .... 
10,  11.  Cadmium,  Bismuth,  . 

12.  Lead,  .  ... 

13.  Mercury,          .  .  . 

14.  Copper,  .  .  . 

15.  Titanium,         .  .  . 

16.  Tin,     .... 

17.  Molybdenum, .  .  . 

18.  Tungsten,        .  .  . 
19,20.  Vanadium,  Tellurium,       . 

21.  Antimony, 

22.  Arsenic,  .  .  . 

2.  Noble  Metals. 

1.  Platinum,  Iridium,  Palladium, 

2.  Gold,     .... 

3.  Silver,    .... 

8.  Supplement  to  the  description  of  minerals, 

CHAP.  VII. — ROCKS  OR  MINERAL  AGGREGATES, 


CHAP.  IX. — BRIEF  NOTICE  OF  FOREIGN  MINING  REGIONS, 
CHAP.  X. — MINERALOGICAL  IMPLEMENTS,  . 
CHAP.  XI.  —WEIGHTS,  MEASURES,  AND  COINS,       • 
TABLES  FOR  THE  DETERMINATION  OF  MINERALS,    . 
INDEX,      .       '"A'* 


132 
132 
141 
143 
143 
150 
158 
160 
160 
161 
172 
194 
196 


202 
206 
209 
211 
233 
243 
247 
250 
257 
259 
270 
273 
290 
294 
298 
299 
300 
301 
304 

307 
311 
319 
329 

335 


CHAP.  VIII. — CATALOGUE  OF  AMERICAN  LOCALITIES  OF  MINERALS,     358 


377 
382 

384 
388 
415 


GLOSSARY  AND  INDEX  OF  TERMS.* 


ACICULAR,  [Lat.  acus,  a  needle,]  53 

Adamantine,  56. 

Adit.  [Lat.  aditus,  an  entrance.] 
The  horizontal  entrance  to  a 
mine. 

Alkali.  An  oxyd  having  an  acrid 
taste,  and  caustic ;  as  potash, 
soda. 

Alkaline.     Like  an  alkali. 

Alliaceous,  [Lat.  allium,  garlic,]  66. 

Alloy.  A  mixture  of  different  met- 
als (excluding  mercury)  by  fusion 
together.  Also,  the  metal  used 
to  deteriorate  another  metal  by 
mixture  with  it. 

Alluvial.  [Lat.  alluo,  to  wash  over.] 
Of  river  or  fresh-water  origin. 

Amalgam.  [Gr.  malagma,  a  sof- 
tened substance  ]  A  compound 
of  mercury  and  another  metal. 

Amalgamation,  326. 

Amorphous,  [Gr.  a,  not,  and  morphe, 
shape,]  54. 

Amygdaloidal,  339. 

Anhydrous.  [Lat.  a,  not,  and 
hudvr,  water.]  Containing  no 
water. 

Arborescent.  [Lat.  arbor,  tree.] 
Branching  like  a  tree. 

Arenaceous.  [Lat.  arena,  sand.] 
Consisting  of,  or  having  the  gritty 
nature  of,  sand. 

Argentiferous.  [Lat.  argcntum, 
silver.]  Containing  silver. 

Argillaceous.  [Lat.  argilla,  clay.] 
Like  clay  ;  containing  clay 

Arsenical  odor,  66. 

Asparagus  green.  Pale  green,  with 
much  yellow. 

Assay.  [Same  etymology  as  essay.] 
To  test  ores  by  chemical  or  blow- 
pipe examination  ;  said  to  be  in 
the  dry  way,  when  doue  by  means 
of  heat,  (as  in  a  crucible,)  and  in 
the  wet  way,  when  by  means  of 
acids  and  liquid  tests. 


The  material  under  chem- 
ical or  blowpipe  examination. 

Astringent,  66. 

Asteriated.  [Gr.  aster,  star.]  Hav- 
ing the  appearance  of  a  star 
within. 

Augitic.     Containing  augite. 

Auriferous.  [Lat.  aurum,  gold.) 
Containing  gold. 

Axes,  24 ;  of  double  refraction,  59. 

Basaltic,  339. 

Bath  stone.  A  species  of  limestone  ; 
called  also  Bath  oolite  ;  named 
from  the  locality,  in  England. 

Bevelment,  beveled,  35. 

Bitter,  66. 

Bittern,  106. 

Bituminous.  Containing  bitumen ; 
like  bitumen. 

Bladed.     Thin  blade-like. 

Blast  furnace,  233. 

Blowpipe,  67  ;  tests,  69, 70  :  imple- 
ments, 68,  69. 

Blue-John.  Narrfe  for  fluor  spar, 
used  in  Derbyshire,  where  it  oftea 
has  a  bluish-purple  color. 

Botryoidal,  [Gr.  botrus,  a  bunch  of 
grapes,]  53. 

Boulder,  bowlder.  Loose  rounded 
mass  of  stone. 

Breccia. 

Brittle,  53,  65. 

Calcine.  [Lat.  calx,  burnt  lime- 
stone.] To  heat,  in  order  to  drive 
off  volatile  ingredients,  and  make 
easy  to  be  broken  or  pounded. 

Calcination.  The  process  of  cal- 
cining. 

Carat,  62. 

Carbon.     Pure  charcoal. 

Carbonate.  A  salt  containing  car- 
bonic acid.  Carbonated ;  con- 
taining carbonic  acid,  as  carbo- 
nated springs. 


*  The  number  after  a  word  signifies  the  page  where  it  is  explained. 
The  etymology  i?  given  in  brackets,  wherever  it  was  deemed  important. 


Vlll 


GLOSSARY    AND    INEEX    OF    TEEMS. 


Carbonize.     To  convert  into  char- 
coal. 
Carburet.     A  compound  of  an  ele  • 

ment  with  carbon,  not  acid. 
Catalan  forge,  237. 
Celandine  green.     Green  with  blue 

and  gray ;  from  the  plant  called 

celandine. 
Cementation,  238. 
Chalybeate.      Impregnated    with 

iron,  80. 
Chert.    A  siliceous  stone  containing 

some  lime  ;  also,  hornstone. 
Chlorid.     Combination  of  an  ele- 
ment with  chlorine. 
Chloride.     Containing  chlorite. 
Chromate.    A  salt  containing  chro- 
mic acid. 
Cinereous.       [Lat.    cinis,    ashes.] 

Resembling  ashes. 
Cleavage  33. 
Coke,  90. 
Columnar,  52. 
Compound  crystals,  42. 
Conchoidal,  65. 
Coralloidal.    Having  a  resemblance 

to  coral. 
Cretaceous.     [Lat.    creta,   chalk.] 

Pertaining  to  chalk. 
Cropping  out.     The  rising  of  layers 

of  rock  to  the  surface. 
Crucible.     [Lat.  crux,  a  cross.]    A 

pot  made  of  earth  or   clay   for 

melting,  or  reduction. 
Cruciform,    [Lat.    crux,  a   cross,] 

43. 
Crystal,  [ Greek  krustallos,  ice,]  19  ; 

systems    of   crystallization,    24, 

32. 

Cube,  25. 

Cupel,  cupellation,  317,  328. 
Cupreous.     [Lat.  cuprum,  copper.] 

Containing  copper. 
Curved  crystals,  42. 
Decrepitate.     To  crackle  and   fly 

apart  when  heated. 
Deflagrate.     To   burn   with   vivid 

combustion. 
Deliquesce.     To  change  to  a  liquid, 

on   exposure  ;  arising  from  the 

attraction  of  moisture. 
Dendrites.      [Gr.    deridron,   tree.] 


Delicate  delineations  branching 
like  a  tree  ;  due  to  infiltration  of 
oxyd  of  iron  or  manganese. 

Density.     Specific  gravity. 

Desiccate.  To  dry,  to  exhaust  of 
moisture. 

Diaphaneity,  58. 

Dichroism,  57. 

Dimetric  system,  32. 

Dimorphism,  44. 

Divergent,  53. 

Disintegrate.  To  fall  to  pieces  ;  a 
result  of  exposure  and  partial  de- 
composition. 

Disseminated.  Scattered  through 
a  rock  or  gangue. 

Dodecahedron,  rhombic,  25  ;  isos- 
celes,39,  fig.  65  ;  pentagonal  37  ; 
scalene,  40. 

Dolomitic.     Pertaining  to  dolomite. 

Dressing  of  ores.  The  picking  and 
sorting  of  ores,  and  washing  pre- 
paratory to  reduction. 

Drusy,  54. 

Dull,  56. 

Earthy.  Soft  like  earth,  and  with- 
out luster. 

Ebullition.     The  state  of  boiling. 

Effervescence,  67. 

Effloresce.  To  change  to  a  state 
of  powder,  by  exposure  ;  arises 
from  the  escape  of  water. 

Elastic,  53,  65.  Electricity  of  min- 
erals, etc.,  62. 

Elements,  72. 

Ellipsoid,  42. 

Elutriation.  [Lat.  elutrio,  to  pour 
from  one  vessel  to  another.] 
Mixing  a  powdered  ^substance 
(as  powdered  flint)  with  water, 
and  then  after  the  coarser  parti- 
cles have  subsided,  carefully  de- 
canting the  liquid  and  putting  it 
away  to  settle,  in  order  to  obtain 
the  impalpable  powder  which  is 
finally  deposited. 

Elvan,  In  Cornwall,  the  granite 
masses  forming  broad  veins  in 
the  killas,  and  containing  the 
stockwerks. 

Enamel.     A  glass  having  an  ap- 


GLOSSARY    AND    INDEX    OF    TERMS. 


ix 


pearance   like  porcelain,  or  like 

the  surface  of  a  tooth. 
Evaporate.     To  become  a  vapor ; 

to  cause  to  become  a  vapor. 
Even  fracture,  65. 
Exfoliate.     To  separate  into  thin 

leaves,  or  to  scale  off. 

Fault.  Dislocation  along  a  fissure, 
as  often  in  coal  beds,  87. 

Feldspathic.  Containing  feldspar 
as  a  principal  ingredient ;  con- 
sisting of  feldspar. 

Ferruginous.  [Lat.  ferrum,  iron.] 
Containing  iron. 

Fetid,  66. 

Fibrous,  52. 

Filament.     A  thread-like  fiber. 
Finery  furnace.     A  furnace  used 
in  the  conversion  of  cast  iron  into 
bar  iron. 

Filiform,  [Lat.Jilum,  a  thread,]  53. 

Flexible,  53,  65. 

Fluate.     Containing  fluoric  acid. 

Fiux.  [Lat.fluo,  to  flow,]  69. 

Foliaceous,  53. 

Forct  ps,  Platinum,  69. 

Fracture  of  mineral?,  65. 

Friable.  Easily  crumbling  in  the 
fingers. 

Fundamental  forms,  23. 

Furnace,  blast,  233  ;  reverberatory, 
327 ;  Catalan,  237. 

Gallery.  A  horizontal  passage  in 
mining. 

Gangue,  204. 

Gelatinize,  67. 

Geniculate.  [Lat.  genu,  knee.] 
Bent  at  an  angle,  43. 

Geode.  [Gr.  gteodes,  earth-like.] 
A  cavity  studded  around  with 
crystals  or  mineral  matter,  or  a 
rounded  stone  containing  such  a 
cavity. 

Glance.  [Germ,  glanz,  luster.] 
Certain  lustrous  metallic  sulphu- 
rets  of  dark  shades  of  color. 

Glimmering.     Glistening,  56. 

Globular,  53. 

Goniometer,  common,  47  ;  reflect- 
ing, 50. 


Granular.     Consisting  of  grains. 
Granulate  ;  to  reduce  to  grains. 

Hackly,  65. 

Hardness,  scale  of,  64. 

Hemihedral  forms,  37. 

Hepatic.  [Gr.  hepar,  liver.]  Hav- 
ing an  external  resemblance  to 
liver. 

Hexagonal  prism,  27. 

Hexagonal  system,  33. 

Homogeneous.  Of  the  same  tex- 
ture and  nature  throughout. 

Hyacinth  red.  Red  with  yellow 
and  some  brown. 

Hyaline.  [Gr.  hualos,  glass.]  Re- 
sembling glass  in  transparency 
and  luster. 

Hydrated.  [Gr.  hudor,  water.] 
Containing  water. 

Ignition.  [Lat.  ignis,  fire.]  The 
state  of  being  so  heated  as  to  give 
out  light ;  at  a  red  or  white  heat. 

Impalpable,  53. 

Implanted  crystals.  Attached  by 
one  extremity. 

Incandescence.     White  heat. 

Incrustation.  A  coating  of  mineral 
matter. 

Indurated.     Hardened  or  solidified. 

Infiltrate.  To  enter  gradually,  as 
water,  through  pores. 

Infusible.  In  mineralogy,  not  fusi- 
ble by  means  of  the  simple  blow- 
pipe. 

Inspissate.     To  thicken. 

Intumesce.     To  froth. 

Investing.  Coating  or  covering,  as 
when  one  mineral  forms  a  coat- 
ing on  another. 

Irised.  [Lat.  iris,  rainbow  ]  Hav- 
ing the  colors  of  the  spectrum. 

Iridescence,  57. 

Isomorphism,  isomorphous,  74. 

Juxtapose.     To  place  contiguous. 

Killas.  In  Cornwall,  the  schistose 
rock  in  which  the  lodes  occur. 

Lamellar,  53. 


GLOSSARY 


INDEX    OF    TERMS. 


Lapidification.  [Lat.  lapis,  a  stone.] 
The  process  of  changing  to  s'one. 

Lapilla.     Small  volcanic  cinders. 

Lavender-blue.  Blue  with  some 
red  and  much  gray. 

Leek-green.  The  color  of  the 
leaves  of  garlic. 

Lenticular.  Thin,  with  acute  edges 
something  like  a  lens,  except  that 
the  surface  is  not  curved. 

Leucitic.     Containing  U-ucite. 

Levigation.  [Lat.  levis,  light.]  The 
process  of  reducing  to  a  fine 
powder. 

Liquation.  [Lat.  liquo,  to  melt  ] 
The  slow  fusion  of  an  alloy,  by 
•which  the  more  fusible  flows  out 
and  leaves  the  rest  behin  1, 328. 

Lithographic  stone.  A  compact 
grayish  or  yellowish-gray  lime- 
stone of  very  even  textuie  and 
conchoidal  fracture  ;  used  in  lith- 
ography. That  of  Solenhofen, 
near  Munich,  is  mo?t  noted. 

Lithology.  [Gr.  lithos,  stone,  and 
logos,  a  discourse.]  Mineralogy. 

Lixiviate.  [Lat.  lixivium,  lye.] 
To  form  a  lye,  by  allowing  water 
to  stand  upon  earthy  or  alkaline 
material,  and  draining  it  off  be- 
low, after  it  has  dissolved  the  sol- 
uble ingredients  present. 

Lode.  [Sax.  Icedan,  to  lead.]  In 
mining,  a  vein  of  mineral  ?ub- 
stance  ;  usually  a  vein  of  metallic 
ore.  The  lode  is  said  to  be  dead 
when  the  material  affords  no 
metal. 

Lodestone,  217. 

Made.  A  compound  crystal,  or  one 
having  a  tesselated  structure. 

Magnesian.    Containing  magnesia. 

Magnetism  of  minerals,  63. 

Malleable,  [Lat.  malleus,  a  ham- 
mer,] 65. 

Mammillary,  [Lat.  mammilla,  a 
little  teat,]  53. 

Manganesian.  Containing  man- 
ganese. 

Marly.  Having  the  nature  of  marl 
containing  marl. 


Massive.  Compact,  and  having  no 
regular  form. 

Matrix.  [Lat.  matrix,  from  mater, 
mother.]  The  rock  or  earthy 
material,  containing  a  mineral  or 
metallic  ore. 

Metallic,  55,  56.  Metallic-pearly, 
55.  Metallic-adamantine,  56. 

Metalliferous.     Yielding  rnetal. 

Metallurgy.  [Gr.  metallon,  and 
ergon,  work.]  The.  science  of 
the  reduction  of  ores. 

Micaceous,  53. 

Mineralized.  Changed  to  mineral 
by  impregnation  with  mineral 
matter.  Also  being  di-guised  in 
character  by  combination  with 
other  substances ;  thus  used  with 
regard  to  metals  when  in  combi- 
nation with  sulphur,  ar  enic,  car- 
bonic acid, or  anything  that  affects 
their  malleability  and  other  qual- 
ities. 

Molecules,  42. 

Molybdate.  A  salt  containing 
molybdie  acid. 

Monoclinate,  33. 

Monometric,  32. 

Mountain  limestone.  A  limestone 
of  the  lower  part  of  the  coal  se- 
ries ;  called  also  carboniferous 
limestone. 

Muffle,  317. 

Nacreous.     Like  pearl. 

Native  metal,  202. 

Nitrate.  A  salt  containing  nitric 
acid. 

Nitriary,  102. 

Nucleus.  The  center  particle  or 
mass  around  which  matter  is  ag- 
gregated. 

Ochreous.     Like  ocher. 
Octahedron,  pp.  23,  25,  26. 
Octahedral.    Having  the  form  of  an 

octahedron. 

Odor  of  minerals,  p.  66. 
Oolite.     [Gr.  oon,  egg,]  p.  349. 
Opalescence,  p.  57. 
Opaline.     Like  opal. 
Opaiized.     Changed  to  opal. 


GLOSSARY    AND    INDEX    OF    TERMS. 


XI 


Opaque,  p.  58. 

Ore,  202.  Also,  by  miners,  a  dis- 
seminated ore  and  the  including 
stone  together  ;  the  term  met- 
al is  often  used  for  the  pure  ore. 

Oxyd,  73. 

Oxydizable.  Capable  of  combining 
with  oxygen. 

Oxydating  flame,  68. 

Pearly  55. 

Percolate.  To  pass  gradually 
through  pores. 

Phosphorescence,  61. 

Pisolitic,  [Lat.pisum,  a  pea,]  com- 
posed of  large  round  grains  or 
kernels,  of  the  size  of  peas. 

Pistachio-green.  Green  with  yel- 
low, and  some  brown. 

Plastic.  Adhesive,  and  capable  of 
being  moulded  in  the  hands. 

Plumose.  Having  the  shape  of  a 
plume,  or  feather. 

Polarisation,  60. 

Polarity,  62. 

Polychroism,  57. 

Piay  of  colors,  57. 

Plutonic  rocks.  Granite  and  allied 
crystalline  rocks. 

Polyhedral.  [Gr.  polus,  many,  and 
Aet/raface.)  Having  many  sides. 

Polymorphism,  44. 

Porous.  Having  minute  vacuities, 
visible  or  invisible  to  the  naked 
eye  ;  a  loose  texture,  allowing 
water  to  filtrate  through. 

Porphyritic.     Like  porphyry,  340. 

Prisms,  23. 

Pseudomorphous,  54. 

Puddling  Furnace.  A  reverbera- 
tory  furnace,  used  in  converting 
cast  into  bar  iron,  after  the  finery 
furnace. 

Pulverize.  [Lat.  pulvis,  dust,]  to 
reduce  to  powder. 

Pulverulent.  Like  a  fine  powder 
slightly  compacted. 

Pyritous.  Having  the  nature  of 
pyrites,  212. 

Pyro-electric,  62. 

Quartation,  318. 


Quartzose.  Containing  quartz  as 
a  principal  ingredient. 

Radiated,  53. 

Rake-vein.  A  perpendicular  min- 
eral fissure. 

Rectangle,  24. 

Reduction  of  ores,  204. 

Reduction  flame,  68. 

Refraction,  58. 

Refractory.  Resisting  the  action 
of  heat  ;  infusible. 

Refrigerate.     To  cool. 

Regulus.  The  pure  state  of  a 
metal,  as  regulus  of  antimony. 

Reniform.     [Lat.  ren,  kiduey,]  53. 

Replacement,  35.     Resinous,  55. 

Resplendent.  Having  a  brilliant 
luster. 

Reticulated.  [Lat.  rete,  a  net,] 
52,54. 

Reverberatory  furnace,  327. 

Rhombohedron,  27. 

Riddling  or  sifting  of  ores.  Put- 
ting the  broken  or  pulverized  ore 
in  a  seive,  and  plunging  the  seive 
into  water,  by  which,  the  whole 
powdered  material  is  raised  by 
the  water  and  the  metallic  part 
sinking  first,  may  be  separated 
to  a  great  extent  from  the  rest. 

Roasting.     Exposing    to    heat   in 

piles,  or  in  a  furnace,  and  thus 

"  driving  offany  volatile  ingredient. 

Saccharoid.  [Gr.  sakchar,  sugar.] 
Having  a  texture  like  loaf  sugar. 

Saline,  (Lat.  sal,  salt.)  Salt  like  ; 
containing  common  salt. 

Salt.  In  chemistry,  any  combina- 
tion of  an  acid  with  a  base,  74. 

Scale  of  hardness,  64. 

Schlich.  The  finely  pulverized  ore 
and  gangue. 

Schistose.  Having  a  slaty  structure. 

Scopiform,  (Lat.  scopa,  a  broom.) 
Like  a  broom  in  form. 

Scoria,  (L.  scoria,  dross,)  205,  341. 

Secondary  forms,  34.     Sectile,  65. 

Semitransparent,  58. 

Shaft.  A  vertical  or  much  in- 
pit,  cylindrical  in  form. 


lii 


GXOSSART    AND    INDEX    OT   TERMS. 


Shale,  341.     Shining,  56. 

Silicate,  74. 

Siliceous.  Consisting  of,  or  con- 
taining silex,  or  quartz. 

Silky,  56. 

Silurian.  A  term  applied  to  the 
fossiliferous  rocks,  older  than 
the  coal  series. 

Slag,  205. 

Smelting  of  iron  ores,  233. 

Spathic,  (Germ,  spath.)    Like  spar. 

Spar.  Any  earthy  mineral  having 
a  distinct  cleavable  structure  and 
some  luster,  as  calcareous  spar. 

Stalactitic,  (Gr.  stalazo,  to  drop  or 
djstil,)  54,  116. 

Stalagmite,  116. 

Specific  gravity,  63. 

Splendent,  56. 

Splintery.  Having  splinters  on  a 
surface  of  fracture. 

Stamping.  Reducing  to  coarse 
fragments  in  a  stamping  mill. 

Stellated,  (Lat.  stella,  star,}  52. 

Strata.     A  series  of  beds  of  rock. 

Streak,  streak-powder,  56. 

Striated.  Lined  or  marked  with 
parallel  grooves,  more  or  lets 
regular. 

Stockwerks.  In  Cornwall,  works 
in  beds  and  veins  of  ore.  The 
works  in  alluvial  deposits  are  dis- 
tinguished as  stream-works. 

Sub.  In  composition,  signifies  be- 
neath ;  also,  somewhat,  or  imper- 
fectly, as  submetallic,  means  im- 
perfectly metallic. 

Sublimation,  (Lat.  sublimis,  high.) 
Rising  in  vapor,  by  heat,  to  be 
again  condensed. 

Submetallic,  55. 

Subtranslucent,  58. 

Subtransparent,  58. 

Subterbrand.  A  name  given  to 
Bovey  coal,  or  brown  coal. 

Subvitreous,  55. 

Sulphate.  A  salt  containing  sul- 
phuric acid. 

Sulphureous,  66. 

Sulphuret.  Combination  of  a  met- 
al with  sulphur. 

Tarnish,  57. 


Tertiary  strata.  Strata  more  re- 
cent in  age  than  the  chalk,  and 
antecedent  to  the  recent  epoch. 

Tesselated,  (Lat.  tessttatus,  che- 
quered.) Chequered. 

Tesseral  system,  (Lat.  tessera,  a 
tour  square  tile,  or  dice,)  32. 

Tetrahedron,  (Gr.  tetra,  four,  he- 
dra,  face,)  37. 

Titaniferous.    Containing  titanium. 

Transition  rocks.  The  older  silu- 
rian,  which  were  formerly  sup- 
posed to  contain  no  trace  of  fos- 
sils. 

Translucent,  58. 

Transparent,  58. 

Triclinate,  33. 

Trimetric,  33. 

Trimorphism,  44. 

Truncation,  truncated,  35. 

Tufaceous.     Like  tufa,  347. 

Tuyeres,  or  twiers,  234. 

Twin  crystals,  42. 

Unctuous.     Adhesive,  like  grease. 

Ustulation.  [L.  ustulatus,  scorch- 
ed, or  partly  burnt.]  Roasting 
of  ores. 

Veins.  In  miner's  use,  small  lodes. 
In  geology,  any  seams  of  rock 
material,  intersecting  strata  crocS- 
wise. 

Vein-stone.  The  gangue  of  a  met- 
al or  mineral. 

Verdigris-green.  Green  inclining 
to  blue  ;  the  color  of  verdigris. 

Vesicular.  Containing  small  va- 
cuities. 

Viscous,  65. 

Vitreous,  (Lat.  vitrum,  glass,)  55. 

Vitrification.     Conversion  to  glass. 

Volatile.  Capable  of  passing  easi- 
ly to  a  state  of  vapor. 

Washing  of  ores.  Exposing  them 
after  stamping,  (or  before  if  in 
fragments,)  to  running  water, 
which  carries  off  the  earthy  ma- 
terial, it  being  lighter  than  the 
ore. 

Zeolitic.  Having  the  nature  of  a 
zeolite,  163. 


MINERALOGY. 


CHAPTER  I. 

GENERAL    CHARACTERISTICS    OF   MINERALS. 

Relations  of  the  three  Depar'men'sof  Nature.  Viewing 
the  world  around  us,  we  observe  that  it  consists  of  rocks, 
earth  or  soil,  and  water  ;  that  it  is  covered  with  a  large  va- 
riety of  plants,  and  tenanted  by  myriads  of  animals.  *  These 
three  familiar  facts  lie  at  the  basis  of  three  primary  branches 
of  knowledge.  The  animals,  of  whatever  kind,  from  the 
animalcule  to  man,  give  origin  to  that  branch  of  science 
which  is  called  Zoology;  the  various  plants,  to  the  sci- 
ence of  Botany ;  and  the  rocks  or  minerals,  to  Mineral* 
ogy.  The  first  two  of  these  departments  embrace  all  natu- 
ral objects  that  have  life,  and  treat  of  their  kinds,  their  vari- 
ties  of  structure,  their  habits,  and  relations. 

The  third  branch  of  knowledge,  Mineralogy,  relates  to 
inanimate  nature.  It  describes  the  kinds  of  mineral  material 
forming  the  surface  of  our  planet,  points  out  the  various 
methods  of  distinguishing  minerals,  makes  known  their  uses, 
and  explains  their  modes  of  occurrence  in  the  earth. 

Importance  of  the  Science  of  Mineralogy.  To  the  un- 
practiced  eye,  the  costly  gem,  as  it  is  found  in  the  rocks, 
often  seems  but  a  rude  bit  of  stone  ;  and  the  most  valuable 
ores  may  appear  worthless,  for  the  metals  are  generally  so 
disguised  that  nothing  of  their  real  nature  is  seen.  There  is 
an  ore  of  lead  which  has  nearly  the  color  and  luster  of  Glau- 
ber salt ;  an  ore  of  iron  that  looks  like  sparry  limestone ; 
an  ore  of  silver  that  might  be  taken  for  lead  ore,  and  an- 
other that  resembles  wax.  These  are  common  cases,  and 

What  classes  of  natural  objects  exist  ?     Of  what  does  Zoology  treat  t 
What  Botany  ?     Of  what  does  Mineralogy  treat  ?    What  advantages 
result  from  the  study  of  minerals  ? 
2 


14  GENERAL   CHARACTERISTICS    OF   MINERALS. 

consequently  much  careful  attention  is  required  of  the  student 
to  make  progress  in  the  science.  Moreover,  a  great  pro- 
portion of  the  mineral  species  are  of  no  special  value,  and 
they  occur  under  so  many  forms  and  colors  that  close  study 
is  absolutely  necessary  in  order  to  be  able  to  distinguish  the 
useless,  and  avoid  being  deceived  by  them;  for  such  decep- 
tions are  common  and  often  lead  to  disastrous  consequen- 
ces in  mining. 

The  science  of  Mineralogy  is,  therefore,  eminently  prac- 
tical. Moreover,  the  very  existence  of  many  of  the  arts  of 
civilized  life,  depends  upon  the  materials  which  the  rocks 
afford.  Besides  the  metals  and  metallic  ores,  we  here  find 
the  ingredients  for  many  common  pigments,  and  for  various 
preparations  used  in  medicine  ;  also  the  enduring  material  so 
valuable  for  buildings  and  numberless  other  purposes  :  more- 
over, from  the  rocks  comes  the  soil  upon  which  we  are  de- 
pendent for  food.  At  the  same  time,  the  student  of  Miner- 
alogy who  is  interested  in  observing  the  impress  of  Infinite 
wisdom  in  nature  around  him,  finds  abundant  pleasure  in 
examining  the  forms  and  varieties  of  structure  which  miner- 
als assume,  and  in  tracing  out  the  principles  or  laws  which 
Creative  power  has  established  even  throughout  lifeless  mat- 
ter, giving  it  an  organization,  though  simple,  no  less  perfect 
than  that  characterizing  animate  beings. 

What  is  a  Mineral  1  It  has  been  remarked  that  Miner- 
alogy, the  third  branch  of  Natural  History,  embraces  every 
thing  in  nature  that  has  not  life.  Is,  then,  every  different 
thing  not  resulting  from  life,  a  mineral  ?  Are  earth,  clay, 
and  all  stones,  minerals  ?  Is  water  a  mineral  ? 

All  the  materials  here  alluded  to  properly  belong  to  the 
mineral  series.  The  minute  grains  which  make  up  a 
bank  of  clay  or  earth,  are  all  minerals,  and  if  their  charac- 
ters could  be  accurately  ascertained,  each  might  be  referred 
to  some  mineral  species.  It  is  evident,  however,  that  the 
clay  itself,  unless  the  grains  are  all  of  one  kind,  is  not  a  dis- 
tinct species,  though  mineral  in  composition  :  it  is  a  com- 
pound mass  or  an  aggregate  of  different  mineral  grains  ;  and 
this  is  true  of  all  ordinary  soil  and  earth.  In  the  same  manner 
very  many  rocks  are  aggregates  of  two  or  more  minerals  in 
intimate  union.  Mineralogy  distinguishes  the  species,  and 
enables  us  to  point  out  the  ingredients  which  are  mixed  in  the 
constitution  of  such  rocks.  It  searches  for  specimens  that 

Is  clay  a  mineral  ?    What  is  the  nature  of  many  rocks  ? 


GENERAL    CHARACTERISTICS    OF    MINERALS.  15 

are  pure  and  undisguised,  ascertains  their  qualities  and  their 
varieties,  and  thus  prepares  the  mind  to  recognize  them 
under  whatever  circumstances  they  may  occur. 

Water  has  no  qualities  which  should  separate  it  from  the 
mineral  kingdom.  All  bodies  have  their  temperature  of  fu- 
sion ;  lead  melts  at  612°  F.  ;  sulphur  at  226°  F. ;  water  at 
32°;  mercury  at  —39°.  No  difference  therefore  of  this 
kind  can  limit  the  mineral  departments. Ice  is  as  properly  a 
rock  as  limestone  ;  and, ;~e re  the  temperature  of  our  globe 
but  a  little  lower  than  it  is,  we  should  rarely  see  water 
except  in  solid  crystal-like  masses  or  layers.  Our  atmos- 
phere, and  all  gases  occurring  in  nature,  belong  for  the  same 
reason  to  the  mineral  kingdom.  Several  of  the  gases  have 
been  solidified,  and  we  can  not  doubt  that  at  some  specific 
temperature  each  might  be  made  solid.  We  can  not,  there- 
fore, exclude  any  substance  from  the  class  of  minerals  be- 
cause at  the  ordinary  temperature  it  is  a  gas  or  liquid. 
Quicksilver  with  such  a  rule  would  be  excluded  as  well  as 
water. 

A  mineral,  then,  is  any  substance  in  nature  not  organized 
by  vitality,  and  having  a  homogeneous  structure.  Thejirst 
limitation  here  stated — not  organized  by  vitality — excludes 
all  living  structures,  or  such  as  have  resulted  from  vital  pow- 
ers ;  and  the  second — a  homogeneous  structure— excludes 
all  mixtures  or  aggregates.  The  different  spars,  gems,  and 
ores  are  minerals,  while  granite  rock,  slate,  clay  and  the 
like,  are  mineral  aggregates.  This  compound  character  is 
apparent  to  the  eye  in  granite,  for  there  is  no  difficulty  in 
picking  out  from  the  mass  a  shining  scaly  mineral,  (mica,) 
and  with  more  attention,  semi-opaque  whitish  or  reddish  par- 
ticles {feldspar)  will  be  easily  distinguished  from  others 
(quartz)  that  have  a  glassy  appearance. 

It  is  a  popular  belief,  that  stones  grow.  Yet  the  absence 
of  any  proper  growth  is  the  main  point  distinguishing  min- 
erals from  objects  that  have  life.  Plants  and  animals  are 
nourished  by  the  circulation  of  a  fluid  through  their  interior  ; 
in  plants,  we  call  the  fluid  sap  ;  in  animals,  blood  ;  and  in- 
crease or  growth  takes  place  by  means  of  material  secreted 
from  this  circulating  fluid.  The  living  being  commences 
with  the  mere  germ,  and  grows  through  youth  to  maturity ; 

Why  should  water  and  gases  rank  with  minerals.  What  is  a  min- 
eral? What  limkations  are  here  implied?  What  is  the  nature  of 
graoite  f 


16  GENERAL   CHARACTERISTICS   OF   MINERALS. 

and  when  this  fluid  finally  ceases  to  circulate,  it  dies  and 
soon  decays. 

Minerals,  on  the  contrary,  have  no  such  nourishing  fluid. 
The  smallest  particle  is  as  perfect  as  the  mountain  mass. 
They  increase  in  size  only  by  additions  to  the  surface  from 
some  external  source.  The  deposit  of  salt  forming  in  an 
evaporating  brine,  has  layer  after  layer  of  particles  added  to 
it,  and  by  this  mode  of  accumulation,  its  thickness  is  at- 
tained. 

Beds  of  an  ore  of  iron,  called  bog  iron-ore,  are  some- 
times said  to  grow.  They  do  in  fact  increase  in  extent. 
Rills  of  water  running  from  the  hills  wash  out  the  iron  in 
the  rocks  they  pass  over,  decomposing  and  altering  the  condi- 
tion of  the  ore,  and  carry  it  to  low  marshy  grounds.  Here  the 
water  becomes  stagnant,  and  gradually  the  iron  is  deposited. 
This  bog  ore,  as  the  name  implies,  is  found  mostly  in  low 
marshy  places,  and  often  contains  nuts,  leaves,  and  sticks, 
changed  to  iron  ore.  The  increase  here  is  obviously  by  ex- 
ternal additions. 

In  limestone  caverns,  and  about  certain  lakes  and  streams, 
the  water  contains  much  carbonate  of  lime.  As  it  evapo- 
rates, layer  after  layer  of  the  lime  is  deposited,  till  thick 
beds  are  sometimes  formed.  In  caverns,  the  water  comes 
dripping  through  the  roofj  drop  by  drop,  and  each  drop 
as  it  dries,  deposits  a  little  carbonate  of  lime.  At  first  it 
forms  but  a  mere  wart  on  the  surface ;  but  it  gradually 
lengthens,  till  it  becomes  a  long  tapering  cylinder,  and 
sometimes  the  pendant  cylinder,  or  stalactite,  as  it  is  called* 
reaches  the  floor  of  the  cave,  and  forms  a  column  several 
feet  in  diameter. 

It  thus  appears  that  minerals  increase,  or  enlarge,  by  ac- 
cretion, or  additions  to  the  surface  only.  They  decrease, 
or  the  surface  is  worn  away,  by  the  action  of  running  water 
and  other  agents.  When  they  decay,  as  sometimes  happens 
from  contact  with  air  and  moisture,  or  some  other  cause,  the 
change  begins  with  the  surface,  and  results  in  producing 
one  or  more  different  minerals.  The  line  of  demarkation, 
therefore,  between  living  beings,  and  minerals  or  inorganic 
matter,  is  strongly  drawn. 

Characters  of  Minerals.     In  pursuing  the  subject  of  min- 

What  are  the  different  modes  of  increase  in  the  animate  and  mineral 
kingdoms?  Mention  examples  of  increase  in  mineral  substances,  and 
explain  the  mode. 


GENERAL    CHARACTERISTICS    OF    MIXERALS.  17 

erals,  there  are  various  qualities  presented  for  our  study. 
We  observe  that  stones  or  minerals  have  color ;  they  have 
hardness  in  different  degrees,  from  being  soft  and  impressi- 
ble by  the  nail,  to  the  extreme  hardness  of  the  diamond ; 
they  have  weight ;  they  have  luster,  from  almost  a  total  ab- 
sence of  the  power  of  reflecting  light  to  the  brilliancy  of  a 
mirror.  Some  are  as  transparent  as  glass  and  others  are 
opaque.  A  few  have  taste.  These  are  the  most  obvious 
characters,  and  characters  to  which  the  mind  would  at  once 
appeal  in  distinguishing  species. 

Other  characters  of  equal  importance  are  found  in  the 
internal  and  external  structure  of  minerals.  On  examining 
a  piece  of  coarse  granite,  we  find  that  each  scale  of  mica 
may  be  split  by  the  point  of  a  knife  into  thinner  leaves. 
Here  is  evidence  of  a  peculiar  structure,  called  cleavage; 
and  wherever  mica  is  found,  this  peculiarity  is  constant. 
The  feldspar  in  the  same  rock,  if  examined  with  care,  will 
be  found  to  break  in  certain  directions  with  a  smooth,  or 
nearly  smooth  plain  surface,  showing  a  luster  approaching 
that  of  glass,  though  somewhat  pearly.  It  is  true  of  feldspar 
also,  that  this  cleavage  is  a  constant  character  for  the  spe- 
cies, as  regards  direction  and  facility.  In  nearly  all  miner- 
als, this  kind  of  structure,  more  or  less  perfect  in  quality, 
may  be  distinguished.  In  a  broken  bar  of  iron  the  irregu- 
larity of  the  grains  proceeds  from  this  cause.  In  granular 
marble,  although  the  mass  as  a  whole  has  no  such  structure, 
the  several  grains  if  attentively  examined  will  be  seen  to 
present  a  distinct  cleavage  structure  and  consequent  angu- 
lar forms.  In  finer  varieties,  the  grains  may  be  so  small 
that  the  characters  cannot  be  observed ;  or  again  the  tex- 
ture of  the  mass  may  be  so  compact  that  not  even  grains 
can  be  distinguished. 

This  cleavage,  then,  is  a  peculiarity  of  internal  structure. 
It  is  intimately  connected  with  another  fact, — that  these  same 
minerals  often  occur  under  the  form  of  some  regular  solid 
with  neat  plane  surfaces ;  and  are  finished  with  a  symmetry 
and  perfection  which  art  would  fail  to  imitate.  These  forms 
are  their  natural  forms,  and  every  mineral  has  its  own  dis- 
tinct system  of  forms.  The  beauty  of  a  cabinet  of  min- 
erals arises  to  a  great  extent  from  the  variety  of  forms  and 

What  physical  characters  are  to  be  observed  in  the  study  of  min- 
erals ?     What  character  depends  on  internal  structure?     Mention  ex- 
amples and  explain.     What  other  character  depends  on  structure  ? 
2* 


18  GENERAL   CHARACTERISTICS    OF   MINERALS. 

high  finish  of  these  gems  of  nature's  workmanship.  The 
mineral  quartz  sometimes  occurs  in  crystals  consisting  of  two 
pyramids  united  by  a  short  six-sided  prism,  and  they  have 
generally  the  transparency  and  almost  the  brilliancy  of  the 
diamond,  whose  name  they  bear  in  common  language.  The 
"  diamonds"  of  central  New  York,  and  many  other  localities, 
are  of  this  kind.  In  other  cases  a  large  surface  of  rock 
sparkles  with  a  splendid  grouping  of  the  pyramidal  glassy 
crystals.  We  might  draw  other  illustrations  from  almost  all 
the  mineral  species.  But  this  will  suffice  to  show  that  in  ad- 
dition  to  the  physical  characters  above  mentioned,  there  are 
others  dependent  on  structure,  which  afford  distinctions  of 
species,  apparent  both  in  external  form  and  internal  clea 
vage. 

Still  other  characters  are  derived  from  subjecting  species 
to  the  action  of  heat,  and  to  acids  or  other  re -agents.  One 
mineral,  when  heated,  melts  ;  another  is  infusible,  or  fuses 
only  on  the  edges  ;  another  evaporates.  By  such  trials,  and 
others  hereafter  to  be  described,  we  study  minerals  in  a  dif- 
ferent way,  and  ascertain  their  chemical  characters.  This 
mode  of  investigation  more  minutely  pursued,  leads  to  a 
knowledge  of  the  constitution  of  minerals,  a  branch  of  study 
which  belongs  properly  to  Analytical  Chemistry  :  the  results 
are  of  the  highest  importance  to  the  mineralogist. 

It  is  perceived,  therefore,  that  the  learner  may  (1)  exam- 
ine into  the  peculiarities  of  structure  among  minerals  ;  (2) 
he  may  attend  to  the  physical  characters  depending  on  light) 
hardness,  and  gravity ;  (3)  he  may  acquaint  himself  with 
the  effects  of  heat  and  chemical  re-agents — the  chemical  char- 
acters. These  are  three  sources  of  distinctions  giving  mu- 
tual aid,  and  a  knowledge  of  all  is  necessary  to  the  miner- 
alogist.  To  learn  to  distinguish  minerals  by  their  color, 
weight,  and  luster,  is  so  far  very  well ;  but  the  accomplishment 
is  of  a  low  degree  of  merit,  and  when  most  perfect,  makes  but 
a  poor  mineralogist.  But  when  the  science  is  viewed  in  the 
light  of  Chemistry  and  Crystallography,  it  becomes  a  branch 
of  knowledge,  perfect  in  itself,  and  surprisingly  beautiful  in 
its  exhibitions  of  truth.  We  are  no  longer  dealing  with 
pebbles  of  pretty  shapes  and  tints,  but  with  objects  modeled 
by  a  Divine  hand ;  and  every  additional  fact  becomes  to  the 
mind  a  new  revelation  of  His  wisdom. 

Mention  examples.  What  other  characters  are  there  ?  Enumerate 
the  kinds  of  characters  presented  by  minerals, 


CRYSTALLOGRAPHY.  19 

In  the  study  of  this  science,  the  learner  will  be  introduced 
first  to  the  structure  of  minerals.  The  subject  is  treated  of 
under  its  usual  name,  crystallography. 


CHAPTER  II. 

CRYSTALLOGRAPHY :    OR    THE    STRUCTURE    OF   MINERALS. 

Crystals :  Crystallization.  The  regular  forms  which 
minerals  assume  are  called  crystals,  and  the  process  by 
which  their  formation  takes  place,  is  termed  crystallization. 

Crystallization  is  the  same  as  solidification.  Whenever 
a  liquid  becomes  solid  there  is  actual  crystallization.  Under 
favorable  circumstances  regular  crystals  may  form ;  but 
very  commonly  the  solid  is  a  mass  of  crystalline  grains,  as 
is  the  case  in  statuary  marble,  or  a  loaf  of  white  sugar.  In 
the  case  of  the  marble,  crystallization  commenced  at  myri- 
ads of  points  at  the  same  instant,  and  there  was  no  room  for 
any  to  expand  to  a  large  size  and  regular  outline.  When 
on  the  contrary,  the  process  is  slow,  simple  crystals  often 
increase  to  a  large  size. 

We  may  understand  this  subject  of  crystallization  by 
watching  a  solution  of  salt,  as  it  evaporates  over  a  fire.  Af- 
ter a  while,  if  the  process  is  not  too  rapid,  minute  points  of 
salt  appear  at  the  surface,  and  these  continue  enlarging. 
They  are  minute  cubes  when  they  begin,  and  they  increase 
regularly  by  additions  to  their  sides,  till  finally  they  become 
so  heavy  as  to  sink.  In  other  cases,  if  the  brine  is  boiled 
awray  too  rapidly,  a  mass  of  salt  may  be  formed  at  the  bot- 
tom of  the  vessel,  in  which  no  regular  crystals  (cubes)  can 
be  seen.  Yet  it  is  obvious  that  the  same  power  of  crystal- 
lization was  at  work,  and  failed  of  yielding  symmetrical 
solids,  because  of  the  rapidity  of  the  evaporation.  Crystals 
of  salt  have  been  found  in  the  beds  of  this  mineral  a  foot 
or  more  in  breadth,  which  had  been  formed  by  natural  evapo- 
ration ;  and  the  whole  bed  is  in  all  cases  crystalline  in  the 
structure  of  the  salt.  However  finely  the  salt  may  be  ground 

Explain  the  terms  crystal  and  crystallization.  Are  solidification  and 
crystallization  the  same  process  ?  Explain  the  different  results  of  crys- 
tallization by  the  example  of  salt.  Is  every  grain,  however  minute, 
crystalline  1 


20  STRUCTURE  OF  MINERALS. 

up,  as  that  for  our  tables,  still  the  grains  were  crystalline  in 
their  origin  and  are  crystalline  in  structure. 

This  subject  may  be  farther  illustrated  by  many  other  sub- 
stances. A  hot  solution  of  sugar  set  away  to  cool,  will  form 
crystals  upon  the  bottom,  or  upon  any  thread  or  stick  in  the 
vessel;  and  these  crystals  will  continue  increasing  till  a 
large  part  of  the  sugar  has  become  crystals.  It  is  a  com- 
mon and  instructive  experiment  to  place  a  delicate  frame- 
work of  a  basket  or  some  other  object,  in  a  solution  of  su- 
gar or  alum  ;  after  a  while  it  becomes  a  basket  of  finished 
gems,  the  crystals  glistening  with  their  many  polished  facets. 
Again,  if  a  quantity  of  sulphur  be  melted,  it  will  crystallize 
on  cooling.  To  obtain  distinct  crystals,  the  surface  crust 
should  be  broken  as  soon  as  formed,  and  the  liquid  part 
within  be  poured  out ;  the  cavity,  when  cold,  will  be  found 
to  be  studded  with  delicate  needles.  The  crust  in  this  case 
is  as  truly  crystallized  as  the  needles,  although  but  faint  tra- 
ces of  a  crystalline  texture  are  apparent  on  breaking  it. 
This  was  owing  to  too  rapid  cooling.  Melted  lead  and  bis- 
muth will  crystallize  in  the  same  manner.  There  is  a  sub- 
stance, iodine,  which  when  heated  passes  into  the  state  of  a 
vapor;  on  cooling  again,  the  glass  vessel  containing  the 
vapor  is  covered  with  complex  crystals,  as  brilliant  as  pol- 
ished steel.  During  the  cold  of  winter,  the  vapors  constitu- 
ting clouds,  often  become  changed  to  snow  ;  this  is  a  similar 
process  of  crystallization,  for  every  flake  of  snow  is  a  con- 
geries of  crystals,  and  often  they  present  the  forms  of  regu- 
lar six-sided  stars.  So  also,  our  streams  become  covered 
with  ice  ;  and  this  is  another  form  of  the  crystallization  of 
water. 

The  power  which  solidifies,  and  the  power  which  crystal- 
lizes, are  thus  one  and  the  same.  Crystallography,  there- 
fore, is  not  merely  a  science  treating  of  certain  regular  so- 
lids in  Mineralogy;  it  is  the  science  of  solidification  in 
general. 

Modes  of  Crystallization.  In  the  above  examples  we 
have  presented  three  different  modes  of  crystallization.  In 
one  case,  the  substance  is  in  solution  in  water,  (or  some  sol- 
vent :)  the  particles  are  thus  free  to  move,  and  as  the  solvent 
passes  off  by  evaporation,  they  unite  and  form  the  crystal- 
Explain  the  case  of  sulphur.  Give  instances  of  crystals  forming  from 
vapor.  What  does  the  science  of  crystallography  embrace?  What 
are  the  modes  of  crystallization  alluded  to  in  the  examples  given  ? 


CRYSTALLOGRAPHY.  21 

lizing  solid.  In  a  second  case,  the  substance  is  fused  by 
heat ;  here  again  the  particles  are  free  to  move  as  long  as 
the  heat  remains ;  and  when  it  passes  off  solidification  com- 
mences, under  the  power  of  crystallization.  In  a  third  case, 
the  substance  is  reduced  to  a  vapor  by  heat ;  and  from  this 
state — also  one  of  freedom  of  motion  among  the  particles — 
it  crystallizes  as  the  heated  condition  is  removed. 

In  the  hardening  of  steel,  it  is  well  known  that  the  coarse- 
ness of  the  grains  varies  with  the  temperature  used,  and  the 
manner  in  which  the  process  is  conducted.  An  increased 
coarseness  of  structure,  implies  that  certain  of  the  crystal- 
line grains  were  enlarged  at  the  expense  of  others.  It 
teaches  us  that  in  some  cases  the  powers  of  crystallization 
may  act  at  certain  temperatures,  even  without  fusion  or  so- 
lution. The  long  continued  vibration  of  iron,  especially 
when  under  pressure,  produces  a  similar  change  from  a  fine 
to  a  coarse  texture  ;  and  this  fact  has  been  the  cause  of  ac- 
cidents in  machinery,  by  rendering  the  iron  brittle  :  it  has 
led  to  the  fracture  of  the  axles  of  rail  cars  and  of  grind- 
stones, and  even  the  iron  rails  of  a  road  may  thus  become 
weak  and  useless. 

By  these  several  processes,  the  various  minerals  and  very 
many  of  the  widely  extended  rocks  of  our  globe,  have  been 
brought  to  their  present  state. 

Perfect  crystals  are  usually  of  moderate  size,  and  gems  of 
the  finest  water  are  quite  small.  As  they  enlarge  they  be- 
come less  clear,  or  even  opaque,  and  the  faces  lose  their 
smoothness  and  much  of  their  luster.  The  emerald,  suffi- 
ciently pure  for  jewelry,  seldom  exceeds  an  inch  in  length, 
and  is  rarely  as  large  as  this ;  but  a  crystal  of  this  species 
(of  the  variety  beryl)  was  obtained  a  few  years  since  at 
Acworth,  New  Hampshire,  which  measured  4  feet  in  length 
and  2£  feet  in  circumference  ;  it  was  regular  in  its  form,  yet, 
except  at  the  edges,  opaque.  The  clear  garnets,  fit  for  set- 
ting, are  seldom  half  an  inch  through  ;  but  coarse  crystals 
have  been  found  6  inches  in  diameter.  Transparent  sap- 
phires also,  over  an  inch  in  length,  are  of  extreme  rarity ; 
but  opaque  crystals  occur  a  foot  or  more  long. 

Quartz  crystals  attain  at  times  extraordinary  dimensions. 
There  is  one  at  Milan  which  is  3£  feet  long  and  5^  in  cir- 
cumference, and  it  weighs  870  pounds.  From  a  single  cav- 

Is  fluidity  essential  to  the  process  of  crystallization  1  What  is  said 
of  steel  and  iron  ?  What  is  said  of  the  size  and  perfection  of  crystals  1 


22  STRUCTURE  OF  MINERALS. 

ity  at  Zinken,  in  Germany,  1000  cwt.  of  crystals  of  quartz 
were  taken  above  a  century  since.  These  facts  indicate  im- 
perfectly the  scale  of  operations  in  the  laboratory  of  nature. 
The  same  process  by  which  a  single  group,  like  that  just  alluded 
to,  has  been  formed,  has  filled  numberless  similar  cavities  over 
various  regions,  and  distributed  the  quartz  material  through 
vast  deposits  in  the  earth's  structure.  The  same  power 
presides  alike  over  the  solidification  of  liquid  lavas,  and  the 
formation  of  a  cube  of  salt,  producing  the  crystalline  grains 
constituting  the  former,  and  the  structure  and  symmetrical 
faces  of  the  latter. 

Constancy  of  Crystalline  Forms.  Each  mineral  may  be 
properly  said  to  have  as  much  a  distinct  shape  of  its  own,  as 
each  plant  or  each  animal,  and  may  be  as  readily  distin- 
guished by  the  characters  presented  to  the  eye.  Crystals 
are,  therefore,  the  perfect  individuals  of  the  mineral  kingdom. 
The  mineral  quartz  has  a  specific  form  and  structure,  as  much 
as  a  dog,  or  an  elm,  and  is  as  distinct  and  unvarying  as  re- 
gards essential  characters,  although,  owing  to  counteracting 
causes  during  formation,  these  forms  are  not  always  assumed. 
In  whatever  part  of  the  world  crystals  of  quartz  may  be  col- 
lected, they  are  fundamentally  identical.  Not  an  angle  will 
be  found  to  differ  from  those  of  crystals  obtained  in  any  part 
of  this  country.  The  sizes  of  the  faces  vary,  and  also  the 
number  of  faces,  according  to  certain  simple  laws  hereafter 
to  be  explained  ;  but  the  corresponding  angles  of  inclina- 
tion are  essentially  the  same,  whatever  the  variations  or  dis- 
tortions. 

Other  minerals  have  a  like  constancy  in  their  crystals,  and 
each  has  some  peculiarity,  some  difference  of  angle,  or  some 
difference  of  cleavage  structure,  which  distinguishes  it  from 
every  other  mineral.  In  many  cases,  therefore,  we  have  only 
to  measure  an  angle  to  determine  the  species.  Both  quartz  and 
carbonate  of  lime  crystallize  at  times  in  similar  six-sided 
prisms  with  terminal  pyramids  ;  but  the  likeness  here  ceases ; 
for  the  angles  of  the  pyramids  are  quite  different,  and  also 
the  internal  structure.  Idocrase  and  tin  ore  crystallize  in 
similar  square  prisms,  with  terminal  pyramidal  planes  ;  but 
though  similar  in  general  form,  each  has  its  own  character- 
istic angles  of  inclination  between  its  planes,  which  angles 

What  is  said  of  the  generality  of  the  power  of  crystallization  ?  What 
is  said  of  the  constancy  of  the  crystalline  forms  and  structure  of  minerals  ? 
Explain  by  the  mineral  quart/,  as  an  example. 


\ 


CRYSTALLOGRAPHY.  2d 

admit  of  no  essential  variation.  Upon  this  character,  the 
constancy  of  crystalline  forms,  depends  the  importance  of 
crystallography  to  the  mineralogist. 

FUNDAMENTAL    FORMS    OF    CRYSTALS. 

The  forms  of  crystallized  minerals  are  very  various.  To 
the  eye  there  often  seems  to  be  no  relation  between  different 
crystals  of  the  same  mineral.  Yet  it  is  true  that  all  the  va- 
rious shapes  are  modifications  according  to  simple  laws  of 
a  few  fundamental  forms.  There  is  perhaps  no  mineral 
which  presents  a  greater  variety  of  form  than  calc  spar. 
Dog-tooth  spar  is  one  of  its  forms  ;  nail-head  spar,  as  it  is 
sometimes  called,  is  another  ;  the  one,  a  tapering  pyrimadal 
crystal,  well  described  in  its  name,  the  other  broad  and  thin, 
and  shaped  much  like  the  head  of  a  wrought-nail.  Yet  both  of 
these  crystals  and  many  others  are  derived  from  the  same  fun- 
damental form.  After  a  few  trials  with  a  knife,  the  student 
will  find  that  slices  may  be  readily  chipped  off  from  the  crys- 
tals of  this  mineral  in  three  directions  ;  and  the  process  will 
obtain  a  solid  from  each,  the  one  identical  with  the  other  in 
(ts  angles.  They  consequently  have  the  same  nucleus  or 
fundamental  form. 

The  fundamental  forms  are  those  from  which  all  the  other 
forms  of  crystals  are  derived.  The  derivative  forms,  are 
called  secondary  forms,  and  their  planes,  secondary  planes. 

The  number  of  fundamental  forms  indicated  by  cleavage, 
is  thirteen.  They  are  either  prisms,*  octaJiedrons  or  dode- 
cahedrons. 

The  prisms  are  either  four-sided  or  six-sided.  The  prisms 
are  denominated  right  prisms,  when  they  stand  erect,  and 
oblique  prisms,  when  they  are  inclined.  Figures  4,  5,  7,  8, 
are  right  prisms,  and  figures  12,  14,  are  oblique  prisms. 
The  sides  in  each  case  are  called  lateral  planes,  and  the 
extremities  bases. 

An  octahedron^  has  eight  sides,  and  consists  of  two  equal 

How  do  the  crystals  of  different  minerals  differ  ?  Mention  exam- 
ples. What  is  said  of  the  forms  of  crystals  of  the  same  mineral  ? 
What  is  understood  by  fundamental  forms  ?  What  by  secondary  forms 
or  planes  ?  How  many  fundamental  forms  are  there  ?  What  kinds  of 
prisms  are  there  ]  Explain  the  terms  lateral  planes  and  bases. 

*  Any  column,  however  many  sides  it  may  have,  is  called  a  prism, 
t  From  the  Greek  okto,  eight,  and  hedra,  face. 


24 


STRUCTURE    OF    MINERALS. 


four-sided  pyramids  placed  base  to  base.  (Figs.  2,  6,  9.)  The 
plane  in  which  the  pyramids  meet  is  called  the  base  of  the 
octahedron ;  (bb,  fig.  6 ;)  the  edges  of  the  base  are  called 
the  basal  edges,  and  the  other  edges  the  pyramidal. 

The  dodecahedron*  has  twelve  sides  (fig.  3.) 

The  axes  of  these  solids  are  imaginary  lines  connecting 
the  centers  of  opposite  faces,  of  opposite  edges,  or  of  oppo- 
site angles.  The  inclination  of  two  planes  upon  one  another 
is  called  an  interfacial  angle. f 

The  figures  here  added  represent  the  forms  of  the  bases 
and  faces  referred  to  in  the  following  paragraphs. 

A  B  C  DBF 


A,  a  square,  having  the  4  sides  equal ;  B,  a  rectangle,  dif- 
fering from  A,  in  having  only  the  opposite  sides  equal ;  C,  a 
rhomb,  having  the  angles  oblique  and  the  sides  equal  ;  D,  a 
rhomboid,  differing  from  the  rhomb  in  the  opposite  sides  only 
being  equal ;  E,  an  equilateral  triangle,  having  all  the  sides 
equal ;  F,  an  isosceles  triangle,  having  two  sides  equal. 
The  lines  crossing  from  one  angle  to  an  opposite  are  called 
diagonals. 

The  fundamental  forms  of  crystals,  though  thirteen  in  num- 
ber, constitute  but  six  systems  of  crystallization,  as  follows  : — 

What  is  an  octahedron  ?  What  is  its  base  ?  How  are  the  basal  and 
pyramidal  edges  distinguished  ?  What  is  a  dodecahedron  ?  What  are 
axes?  What  are  interfacial  angles?  Explain  the  terms  square  ;  rect- 
angle ;  rhomb  ;  rhomboid  ;  equilateral  triangle  ;  isosceles  triangle  ; 
diagonal.  How  many  systems  of  crystallization  are  there? 

*  From  the  Greek  dodeka,  twelve,  and  hedra,  face, 
t  An  angle  is  the  amount  of  divergence  of  two  straight  lines  from  a 
given  point,  or  of  two  planes  from  a  given  edge.  In  the  annexed  figure, 
ACB  is  an  angle  formed  by  the  divergence  of  two 
lines  from  C.  If  a  circle  be  described  with  the 
angular  point  C  as  the  center,  and  the  circumference 
DABFE  be  divided  into  360  equal  parts,  the  number 
of  these  parts  included  between  A  and  B  will  be  the 
number  of  degrees  in  the  angle  ACB  ;  that  is,  if  40 
of  these  parts  are  included  between  A  and  B,  the 
angle  ACB  equals  40  degrees  (40°).  DF  being 
perpendicular  to  EB,  these  two  lines  divide  the  whole  into  4  equal  parts, 
and  consequently  the  angle  DCB  equals  360°-f-4  equals  90°.  This  is 
termed  a  right  angle.  An  angle  more  or  less  than  90°  is  called  an 
oblique  angle  ;  if  less,  as  ACB,  an  acute  angle ;  if  more,  as  ACE,  an 
obtuse  angle. 


FUNDAMENTAL    FORMS    OF    CRYSTALS. 


I.  The  first  system  includes  the  cube  (fig.  1  or  la,  the  lat- 
ter in  outline  ;)  regular  octahedron  (fig.  2 ;)  and  the  rhombic 
1  la  2 


dodecahedron  (fig.  3  or  3a.)  They  are  symmetrical  solids 
throughout,  in  all  positions,  being  alike  in  having  the  height, 
breadth  and  thickness  equal ;  their  three  axes,  represented  by 
the  dotted  lines  in  the  figures,  are  at  right  angles  with  one 
another  and  equal.  In  the  cube,  the  axes  connect  the  cen- 
ters of  opposite  faces  ;  in  the  octahedron  and  dodecahedron, 
they  connect  the  apices  of  solid  angles.  This  is  more  fully 
explained  on  a  following  page. 

The  cube  has  its  faces  equal  squares,  and  its  angles  all 
right  angles. 

The  octahedron  has  its  8  faces  equal  equilateral  triangles  : 
its  edges  are  equal ;  its  plane  angles  are  60°  ;  its  interfacial 
angles  (angles  between  adjacent  faces)  109°  28'. 

The  dodecahedron  has  its  12  faces  equal  rhombs  ;  the 
edges  are  equal;  the  plane  angles  of  the  faces  are  109°  28' 
and  70°  32' ;  its  interfacial  angles  are  120°. 

II.  The  second  system  includes  the  right  square  prism 
456 


(figs.  4  and  5,)  and  square  octahedron  (fig.  6.)     They  have 
two  equal  lateral  axe?,  and  a  vertical  axis  unequal  to  the 

What  forms  does  the  first  system  include  ?  How  are  these  forms 
related  ?  Describe  the  forms.  What  forms  does  the  second  system 
include,  and  how  are  they  related  1  Describe  the  forms. 

3 


STRUCTURE    OF    MINERALS. 


lateral  :  that  is,  the  width  and  breadth  are  equal,  but  the 
height  is  varying.  All  the  axes  are  at  right  angles  with  one 
another.  Fig.  4  is  a  square  prism  higher  than  its  breadth, 
and  fig.  5  is  one  shorter  than  its  breadth. 

The  right  square  prism  and  square  octahedron  may  be  of 
any  height,  either  greater  or  less  than  the  breadth  ;  but  the 
dimensions  are  fundamentally  constant  for  the  same  mineral 
species.  The  square  prism  has  its  base  a  square.  The 
square  octahedron  has  its  base  (bb)  a  square,  and  its  8  faces 
equal  isosceles  triangles.  The  lateral  edges  of  the  prism 
differ  in  length  from  the  basal ;  and  the  terminal  or  pyra- 
midal edges  of  the  octahedron  differ  in  length  from  the  basal. 

III.  The  third  system  includes  the  rectangular  prism 
(fig.  7,)  the  rhombic  prism  (fig.  8,)  and  the  rhombic  octahe- 
789 


dron  (fig.  9.)  They  are  similar  in  having  the  three  dimen- 
sions, or  the  three  axes,  unequal ;  and  the  axes  at  right  an- 
gles with  one  another. 

The  rectangular  prism  has  a  rectangular  base,  and  the 
axes  connect  the  centers  of  opposite  faces.  The  rhombic 
prism  and  rhombic  octahedron  have  each  a  rhombic  base, 
the  angle  of  which  differs  for  different  species.  The  lateral 
axes  of  the  prism  connect  the  centers  of  opposite  edges, 
and  in  the  octahedron  they  connect  the  apices  of  opposite 
angles. 

IV.  The/our^  system  includes  the  right  rhomboidal  prism 
10  11  12  13 


(figs.  10,  11,)  and  the  oblique  rhombic  prism  (figs.  12,  13.) 
The  lateral  axes  are  unequal,  and  at  right  angles  as  in  the 

What  forms  are  included  in  the  third  system  and  how  are  they  rela- 
ted ?  Describe  the  forma.  What  forms  does  the  fourth  system  include 
and  how  are  they  related  ? 


FUNDAMENTAL    FORMS    OF    CRYSTALS. 


27 


last  system  ;  but  they  are  oblique  to  the  vertical  axes.     Their 
positions  are  shown  in  the  figures. 

The  right  rhomboidal  prism. stands  erect  when  on  its  rhom- 
boidal base,  as  in  fig.  11  ;  but  is  oblique  when  placed  on 
either  of  the  other  sides,  as  in  fig.  10.  The  oblique  rhombic 
prism  is  shown  in  a  lateral  view  in  fig.  12,  and  a  front  view 
in  fig.  13. 

V.  The  fifth  system  includes  the  oblique  rhomboidal  prism 
which  has  the  three  axes  unequal,  14  15 
and  all  are  oblique  in  their  intersec- 
tions.    Fig.   14  represents  a  side 

view  of  this  form,  and  fig.  15  a 
front  view. 

VI.  The  sixth  system  includes 

the  rhombohedron  and  hexagonal  prism,  in  which  there  are 
16  16a  17  17a  18 

m  •  ^~JLL_ 

~H 


three  equal  lateral  axes  and  a  vertical  axis  at  right  angles 
with  the  three.  Fig.  16  is  an  obtuse  rhombohedron,  and  I6a 
is  the  same  in  outline,  showing  the  axes.  Figs.  17,  17a, 
represent  an  acute  rhombohedron.  Fig.  18  is  a  hexagonal 
prism  ;  it  is  bounded  by  six  equal  lateral  planes  ;  the  lateral 
axes  either  connect  the  centers  of  opposite  faces,  as  in  the 
figure,  or  of  opposite  lateral  edges. 

To  understand  the  rhombohedron,  the  student  should  have 
a  model  before  him.  On  examining  it  he  will  find  one  solid 
angle  made  up  of  three  equal  plane  angles,  and  another  op- 
oosite  one  of  the  same  kind  ;  all  the  other  solid  angles  are 
different  'from  these.  These  two  solid  angles  are  called  the 
vertical  solid  angles,  and  a  line  drawn  from  one  to  the  other 
is  the  vertical  axis  of  the  rhombohedron.  The  rhombohe- 
dron should  be  held  with  this  line  vertical ;  it  is  then  said  to 
be  in  position.  Thus  placed,  it  will  be  seen  to  have  six  lat- 
eral angles,  six  equal  lateral  edges,  and  also  six  equal  termi- 
nal edges,  three  of  the  terminal  above  and  three  below. 

What  forms  does  the  fifth  system  include,  and  how  does  this  system 
differ  from  the  preceding  1  What  does  the  sixth  system  include  ? 
What  is  said  of  the  rhorabohedron  ?  of  its  position  ?  its  solid  angles? 


23  STRUCTURE  OF  MINERALS. 

The  lateral  edges  in  figure  17a,  are  distinguished  from 
the  terminal  by  being  made  heavier.  Figure  19  repre- 
sents a  vertical  view  of  fig.  16 ;  19  19a 
the  three  edges  meeting  at  center 
are  the  terminal  edges  of  one  ex- 
tremity :  the  exterior  six  are  the 
lateral  edges  ;  and  the  six  lateral 
angles  are  seen  at  their  intersec- 
tions. In  fig.  19a,  the  same  is 
seen  in  outline,  and  the  dotted  lines  represent  the  three  late- 
ral or  transverse  axes,  connecting  the  centers  of  opposite 
lateral  edges.  The  lateral  and  terminal  edges  differ  in  one 
set  being  acute  and  the  other  obtuse  ;  in  the  obtuse  rhombo- 
hedron  (fig.  16)  the  terminals  are  obtuse,  and  in  the  acute 
rhombohedron  (fig.  17)  they  are  acute. 

Several  of  the  primary  forms  are  easily  cut  from  wood  or 
chalk.  Cut  out  a  square  stick,  and  then  saw  off  a  piece 
from  one  end  as  long  as  the  breadth  of  the  stick  :  this  is  the 
cube.  Saw  off  other  pieces  longer  or  shorter  than  this,  and 
they  are  different  right  square  prisms.  Shave  off  a  piece 
of  more  or  less  thickness  from  one  side  of  the  square  stick, 
and  it  then  becomes  a  rectangular  stick.  From  it,  pieces 
may  be  sawn  off,  of  different  lengths,  and  they  will  be  right 
rectangular  prisms.  Next  cut  a  stick  of  a  rhombic  shape, 
(a  section  having  the  shape  in  figure  C,  page  26,)  from  it 
right  rhombic  prisms  may  be  cut,  of  any  length.  Shave  off 
more  or  less  from  one  side  of  the  rhombic  stick,  and  it  is 
changed  to  a  rhomboidal  form,  (section  as  in  fig.  D,  page  26r) 
and  rhomboidal  prisms  may  be  sawn  from  it  of  any  length. 
Take  a  rhombic  stick  again ;  and  instead  of  sawing  it  off 
straight  across,  as  before,  saw  off  the  end  obliquely  from  one 
side-edge  to  the  opposite  ;  the  base  thus  formed  is  oblique 
to  the  sides  :  then  saw  the  stick  again  in  parallel  oblique  di- 
rections, (accurately  parallel.)  and  an  oblique  rhombic  prism 
will  be  obtained.  If  the  oblique  direction  is  such  that  the 
basal  plane  equals  the  lateral,  the  solid  is  a  rhowbohedron, 
Proceeding  in  the  same  way  with  a  rhomboidal  stick,  oblique 
rhomboidal  prisms  maybe  made.  The  student  is  advised  to 
make  these  solids,  either  from  wood,  raw  potatoes,  or  chalk,* 
in  order  to  become  familiar  with  them. 

What  is  said  of  the  lateral  edges  and  angles  of  the  rhombohedron  1 

*  Models  made  of  chalk  become  quite  hard  if  washed  over  with  a 
strong  solution  of  gum  Arabic,  or  varnish. 


FUNDAMENTAL    FORMS    OF    CRYSTALS.  29 

By  means  of  such  models,  the  student  may  trace  out  im- 
portant relations  between  the  fundamental  forms. 

Take  a  cube,  and  cut  off  each  angle  evenly,  inclining  the 
knife  alike  to  the  adjacent  faces ;  this  produces  figure  20. 
Continue  taking  slice  after  slice  equally  from  each  angle, 
and  the  solid  takes  the  form  in  fig.  20<z,  (called  a  cubo-octahe- 
dron  ;)  still  continue  taking  off  regular  slices  from  each  angle 
alike,  and  it  finally  comes  out  a  regular  octahedron,  the  form 
represented  in  fig.  205.  The  last  diminishing  point  in  each 
20  20a  206 


face  of  the  cube  is  the  apex  of  each  solid  angle  of  the  octa- 
hedron. It  is  hence  apparent  why  the  axes  of  the  cube  con- 
nect the  opposite  solid  angles  of  the  octahedron. 

Take  another  cube  (one  of  large  size  is  preferable)  and 

pursue  the  same  process  with  each  of  the  edges,  keeping  the 

knife,  in  cutting,  equally  inclined  to  the  faces  of  the  cube, 

and  we  obtain,  in  succession,  the  forms  represented  in  figs. 

21  21o  216 


21  and  21a  ;  and  finally  as  the  plane  P  disappears,  it  comes 
out  the  rhombic  dodecahedron,  (fig.  215.)  Hence  the  same 
axes  which  connect  the  centers  of  opposite  faces  in  the  cube, 
connect  opposite  acute  solid  angles  in  the  dodecahedron. 

So  the  cube,  by  reversing  the  process,  may  be  made  from 
an  octahedron  by  cutting  off  its  solid  angles,  passing  in  suc- 
cession through  the  forms  represented  in  figures  20Z>,  200, 
20,  to  figure  1.  The  dodecahedron  also  yields  a  cube  in  a 
similar  manner,  giving  as  the  process  goes  on,  the  forms  rep- 
resented in  figures  215,  21a,  21,  1. 

Moreover,  the  octahedron  and  dodecahedron  are  easily  de- 
How  can  you  make  an  octahedron  from  a  cube  ?     How  make  a  do- 
decahedron from  a  cube  1     How  the  cube  from  an  octahedron  ?  the 
cube  from  a  dodecahedron  7     What  relation  hence  exists  between  the 
solids  of  the  first  system  ? 

3* 


30 


STRUCTURE    OF    MINERALS. 


rived  from  one  another.     Figure  22  represents  an  octahedron 

22  22a        with  the  edges  truncated.     On 

continuing  this  truncation,  the 
planes  A  are  reduced  in  size, 
and  the  form  in  figure  22a  is 
obtained ;  and  another  step  be- 
yond, we  have  the  dodecahedron, 
(fig.  211.)  Figure  22a  repre- 
sents a  dodecahedron  with  the  obtuse  solid  angles  replaced ; 
and  this  replacement  continued,  produces  finally  an  octahe- 
dron, the  reverse  of  the  preceding. 

These  solids  are,  then,  so  related  that  they  are  all  deriva- 
ble from  one  another  ;  and  the  three  actually  are  often  pre- 
sented by  the  same  mineral.  All  the  figures  above  referred 
to,  occur  as  forms  of  galena,  fluor-spar,  and  several  other 
species.  Instead,  therefore,  of  considering  the  three  solids, 
the  cube,  regular  octahedron,  and  dodecahedron,  as  indepen- 
dent forms,  we  properly  speak  of  them  as  constituting  to- 
gether one  system,  or  as  belonging  to  the  same  series  of 
forms. 

Again  :  pursue  the  same  mode  of  dissection  on  the  angles 
of  a  square  prism,  taking  care  to  move  the  knife  parallel  to  a 

23  23a        diagonal  of  the  prism ;  the  form  in 

figure  23  is  first  obtained,  and  final- 
ly a  square  octahedron,  figure  23a. 
The  square  prism  and  square  octa- 
hedron (like  the  cube  and  regular 
octahedron)  belong  to  one  and  the 
same  system.  The  two  often  oc- 
cur in  the  same  mineral. 

Again  :  remove  with  a  knife  the  basal  edges  of  a  rhombic 
24a  prism,  moving  the  knife  parallel  to  a 
diagonal  plane  of  the  prism,  figure  24 
is  at  first  obtained,  and  then  a  rhombic 
octahedron,  (fig.  24a.)  Remove  the 
four  lateral  edges  of  a  rhbmbic  prism, 
(see  fig.  26as)  keeping  the  knife  paral- 
lel to  a  vertical  diagonal  plane  :  the 
form  in  figure  25  will  first  be  obtained,  and  then  a  right  rectan- 
gular prism,  (fig.  25a)  ;  and  conversely  cut  off  the  lateral  edges 

How  can  you  make  a  square  octahedron  from  a  square  prism  ?  How 
a  rhombic  octahedron  from  a  rhombic  prism  1  How  a  rectangular  prism 
from  a  rhombic  ? 


FTTNTDAMENTAL    FOHMS    OF    CRYSTALS. 


a  right  rectangular  prism,  with  the  knife  parallel  to  the  ver- 
25  25a  26 


26« 


tical  diagonal  planes  of  this  prism, 
(as  is  seen  in  fig.  26  )  and  a  right 
rhombic  prism  (fig.  26a)  is  the  re- 
sult. The  relations  of  these  two 
prisms  is  shown  in  figure  26b, 
which  represents  a  rhombic  prism 
within  a  rectangular  prism.  It  is 


obvious  on  comparing  these  figures,  that  the  lateral  axes 
which  connect  the  centers  of  opposite  faces  in  the  rectangu- 
lar prism,  connect  the  centers  of  opposite  lateral  edges  in 
the  rhombic  prism. 

These  three  forms,  the  right  rhombic  prism,  rhombic  oc- 
tahedron, and  rectangular  prism,  are  so  closely  related,  that 
one  may  give  origin  to  the  other,  and  all  may  occur  in  the 
same  mineral.  This  is  often  the  case,  as  in  the  minerals 
celestine  and  heavy  spar. 

Again :  set  the  right  rhomboidal  prism  on  one  of  its  lat- 
eral faces,  and  then  slice  off  each  lateral  edge,  (lateral,  as  so 
situated,)  keeping  the  knife  parallel  with  the  diago-  27 
nal  plane,  and  an  oblique  rhombic  prism  is  obtained. 
Figure  27  represents  the  process  begun,  and  figure 
13,  as  well  as  the  interior  of  figure  27,  the  com- 
pleted oblique  rhombic  prism. 

Lastly  :  take  a  rhombohedron,  and  after  placing 
it  in  position,  fig.  16.)  look  down  upon  it  from  above,  (fig. 
19 ;)  the  six  lateral  edges  are  seen  to  form  a  regular  six-sided 
figure  around  the  axis.  If  these  edges  be  cut  off  parallel 
to  the  axis,  a  six-sided  prism  (having  a  three-sided  pyra- 
mid at  each  extremity)  must,  therefore,  result.  This  pro- 
cess is  shown  begun  in  figure  28,  and  completed  in  figure 

How  is  a  rhombic  prism  derived  from  a  rectangular  ?  What  relation 
hence  between  these  prisms?  How  can  yen  make  an  oblique  rhom- 
bic prism  from  a  right  rhomboidal  ?  How  a  right  rhomboidal  from  an 
oblique  rhombic  ?  Explain  the  relation  b^tw  tn  the  rhombohedroa  and 
hexagonal  prism,  and  how  one  is  reduced  to  iie  other. 


32 


STRUCTURE    OF   MINERALS. 


28fl.  Looking  down  again  on  the  model  as  before,  the  7af- 
eral  angles  are  seen  to  form  six  equi-distant  points  around  the 
axis  ;  and  if  these  angles  are  removed  in  the  same  manner, 
another  six-sided  prism  is  obtained,  differing,  however,  from 
the  former  in  having  the  faces  of  the  pyramid  at  each  end, 
five-sided,  instead  of  rhombic.  Figures  29,  30,  illustrate  the 
process.  Conversely,  we  may  make  a  rhombohedron  out  of 
28  28a  29  30  31 


a  hexagonal  prism,  by  cutting  off  three  alternate  basal  edges 
at  one  extremity  of  the  prism,  and  similarly,  three  at  the 
other  extremity  alternate  with  these,  as  in  figure  31.  In  fig- 
ure 30,  the  process  is  farther  continued,  and  the  rombohedron 
is  shown  as  a  nucleus  to  the  prism.  By  cutting  off  slices 
parallel  with  R,  the  rhombohedron  is  at  last  obtained.  The 
close  relation  of  the  rhombohedron  and  hexagonal  prism  is 
hence  obvious.  Calcareous  spar  has  the  rhombohedron  as  its 
primary,  and  very  often  occurs  in  hexagonal  forms.  The 
same  is  true  of  quartz  and  many  other  species. 

From  the  above  transformations,  the  study  of  which,  with 
the  aid  of  a  knife  and  a  few  raw  potatoes  or  lumps  of  chalk, 
may  afford  some  amusement  as  well  as  instruction,  the  stu- 
dent will  understand  more  fully  the  six  systems  of  crystalli- 
zation.* These  six  systems  have  received  the  following 
names  : 

1.  Monometric  ortesseral  system,  (from  the  Greek  monos, 
one,  and  metron,  measure,  alluding  to  the  three  axes  being 
equal  in  length.)     Includes  the  cube,  octahedron  and  dode- 
cahedron, (figs.  1,  2,  3.) 

2.  Dimetric  system,  (from  dis,  two  times,  and  metron,  al- 
luding to  the  vertical  axis  being  unequal  to  the  other  two.) 

Give  the  names  of  the  systems  of  crystallization,  and  mention  the 
forms  each  includes. 

*  In  some  text  books,  the  student  may  read  about  certain  integral 
forms,  the  cube,  the  three-sided  pyramid  and  three-sided  prism,  from 
which  it  is  stated  all  the  other  forms  may  be  made.  The  idea  of  such 
forms  has -nothing  to  do  with  crystallography,  or  the  actual  constitu- 
tion of  crystals.  '.'•••  .......•- 


CLEAVAGE.  83 

Includes  the  square  prism  and  square  octahedron,  (figs.  4, 
5,6.) 

3.  Trimetric  system,  (from  iris,  three  times,  and  metron, 
alluding  to  the  three  axes  being  unequal.)     Includes  the  right 
rhombic  prism,  right  rectangular  prism  and  rhombic  octahe- 
dron, (figs.  7,  8,  9.) 

4.  Mon&clinate  system,  (from  monos,  one,  and  klino,  to 
incline,  one  axis  being  inclined  to  the  other  two  which  are 
at  right  angles.)     Includes  the  right  rhomboidal  prism  and 
oblique  rhombic  prism,  (figs.  10,  11,  12,  13.) 

5.  Triclinate  system,  (from  tris  and  klino,  the  three  axes 
being  oblique  to  one  another.)     Includes  the  oblique  rhom- 
boidal prism,  (figs.  14, 15.) 

6.  Hexagenal  system.     Includes  the  rhombohedron  and 
hexagonal  prism,  (figs.  16,  17,  18.) 

CLEAVAGE. 

It  has  already  been  stated  that  crystals  of  calcareous  spar 
may  be  chipped  off  easily  in  three  directions,  and  by  this 
means,  the  fundamental  form,  a  rhombohedron,  may  be  ob- 
tained. In  all  other  directions  only  an  irregular  fracture 
takes  place.  This  property  of  separating  into  natural  layers, 
is  called  cleavage,  and  the  planes  along  which  it  takes  place, 
cleavage  joints. 

Cubes  of  fluor  spar  may  be  cleaved  on  the  angles,  with  a 
slight  pressure  of  the  knife,  and  the  process  continued  affords 
successively  the  forms  represented  in  figures  20,  20#,  and 
finally  the  completed  octahedron,  as  already  explained.  A 
lead  ore,  called  galena,  yields  cubes  by  cleavage.  Mica— 
often  improperly  called  isinglass — may  be  torn  by  the  fingers 
into  elastic  leaves  more  delicate  thun  the  thinnest  paper. 

In  many  species  cleavage  is  obtained  with  difficulty,  and  in 
others  none  can  be  detected.  Quartz  is  an  instance  of  the 
latter ;  yet  it  may  sometimes  be  effected  with  this  mineral  by 
heating  it  and  plunging  it  while  hot  into  cold  water. 

The  following  are  the  more  important  laws  with  respect  to 
this  property : 

Cleavage  is  uniform  in  all  varieties  of  the  same  mineral. 

It  occurs  parallel  to  the  faces  of  a  fundamental  form  or 
along  the  diagonals. 

It  is  always  the  same  in  character  parallel  to  similar  faces 

What  is  cleavage  ?  How  does  it  differ  in  different  minerals  ?  What 
are  die  laws  relating  to  cleavage. 


34  STRUCTURE  OF  MINERALS. 

of  a  crystal,  being  obtained  with  equal  ease,  and  affording 
planes  of  like  luster  :  and  conversely,  it  is  dissimilar  paral- 
lel to  dissimilar  planes.  It  is  accordingly  the  same,  parallel 
to  all  the  faces  of  a  cube  ;  but  in  the  square  prism,  the  basal 
cleavage  differs  from  the  lateral,  because  the  base  is  unequal 
to  the  lateral  planes.  Often  there  is  an  easy  cleavage  par- 
allel to  the  base,  and  none  distinct  parallel  to  the  sides,  as 
in  topaz ;  and  so  the  reverse  may  be  true. 

The  thirteen  fundamental  forms  enumerated,  are  the  solids 
obtained  from  the  various  minerals  by  cleavage. 

Some  minerals  present  peculiar  cleavages  of  a  subordinate 
character,  independent  of  the  principal  cleavage.  Calc  spar, 
for  example,  has  sometimes  a  cleavage  parallel  to  the  longer 
diagonal  of  its  faces.  The  facts  on  this  subject  are  of  con- 
siderable interest,  yet  not  of  sufficient  importance  to  be  dwelt 
on  in  this  place. 

SECONDARY    FORMS. 

If  crystals  always  assumed  the  shape  of  the  primary  form, 
there  would  be  comparatively  little  of  that  variety  and  beauty 
which  we  actually  find  in  the  mineral  kingdom.  Nature 
first  taught  to  heighten  the  brilliancy  of  the  gem  by  covering 
its  surface  with  facets.  To  the  uninstructed  eye,  these  cubes 
and  prisms  with  their  numberless  brilliant  surfaces,  often 
appear  as  if  they  had  been  cut  and  polished  by  the  lapidary  -, 
yet  the  skill  and  finish  of  the  work,  most  perfect  in  the 
microscopic  crystal,  has  but  feeble  imitation  in  art.  Not 
unfrequently,  crystals  are  found  with  one  or  two  hundred  dis- 
tinct planes,  and  occasionally  even  a  much  larger  number ; 
and  every  edge  and  angle  has  the  utmost  perfection,  and  the 
surfaces  an  evenness  of  polish,  that  betrays  no  rude  work- 
manship, even  under  the  highest  magnifying  glass.  Cavities 
are  occasionally  met  with  in  the  rocks,  studded  on  every 
side  with  crystals — a  crystal  grotto  in  minature — sparkling 
when  brought  out  to  the  sun  like  a  casket  of  jewels.  Even 
amid  the  apparent  confusion,  there  is  wonderful  order  of 
arrangement  in  the  crystals  :  the  corresponding  planes  gen- 
erally face  the  same  way,  so  that  the  sparkling  effect  appears 
in  successive  flashes  over  the  surface,  as  every  new  set  of 
facets  comes  in  turn  to  the  light.  Add  to  this  view,  their 
delicate  colors — the  rich  purple  of  the  amethyst,  the  soft 
yellowish  shades  of  the  topaz,  the  deep  green  of  the  erne. 

On  what  does  the  beauty  of  crystals  to  a  great  extent  depend '? 


MODIFICATIONS    OF    CRYSTALS.  85 

raid  —  and  it  will  be  admitted  that  the  powers  of  crystalliz- 
ation scarcely  yield  to  vitality  in  the  forms  of  beauty  they 
produce. 

These  results  are  not  more  wonderful  than  the  simplicity 
of  the  laws  that  lead  to  them. 

The  various  secondary  forms  proceed  from  the  occurrence 
of  planes  on  the  angles  or  edges  of  the  fundamental  forms, 
which  planes  are  called  secondary  planes.  Figures  20, 
21,  are  secondaries  to  the  cube,  and  the  planes  a  and  e  are 
secondary  planes  ;  figures  28,  29,  30,  are  secondaries  to 
the  rhombohedron,  and  the  planes  e  and  a  are  secondary 
planes.*  These  secondary  planes  however  numerous,  con- 
form in  their  positions  to  a  certain  law  called  the  law  .of 
symmetry.  Previous  to  stating  this  law  a  few  explanations 
are  added. 

The  cube,  it  has  been  remarked,  has  six  equal  square  faces. 
The  twelve  edges  are  therefore  all  equal,  and  so  also  the 
eight  angles.  In  the  square  prism  the  vertical  edges  differ 
in  length  from  the  basal,  and  are  therefore  not  similar.  In 
the  rectangular  prism,  not  only  the  vertical  differ  from  the 
basal,  but  two  of  the  basal  at  each  extremity  differ  from  the 
other  two  basal.  This  will  be  seen  at  once  in  the  models. 
In  the  right  rhombic  and  rhomboidal,  two  of  the  lateral  edges 
are  acute  and  two  obtuse  ;  these  then  are  not  similar  to  one 
another.  In  the  oblique  prisms  some  of  the  basal  edges  are 
acute  and  some  obtuse.  After  tracing  out  the  similar  and 
dissimilar  angles  and  edges  in  the  primaries,  with  the  models, 
the  following  laws  may  be  easily  applied  :  Either  — 

1.  All  the  similar  parts  of  a  crystal  are  similarly  and, 
simultaneously  modijied  ;*  or,  — 

Explain  the  relation  of  secondary  planes  to  the  fundamental  form. 
What  is  said  of  the,<cube  ?  of  the  square  prism  ?  the  rectangular  prism  ? 
the  right  rhombic  and  rhomboidal  ]  the  oblique  prisms  1  What  is  the  first 
law  repecting  secondary  planes  ? 

.  —  What  is  meant  by  replacement,  bevelment,  and  truncation1? 


*  To  avoid  circumlocutions,  the  following  technical  terms  are  employed 
in  describing  the  modifications  of  crystals. 

Replacement.  An  edge  or  angle  is  replaced,  when  cut  off  by  one  or 
more  secondary  planes,  (figs.  20,  21,  32.) 

Truncation.  An  edge  or  angle  is  truncated,  when  the  replacing 
plane  is  equally  inclined  to  the  adjacent  faces,  (figs.  20,  21.) 

Bevelment.  An  edge  is  beveled,  when  replaced  by  two  planes,  which 
are  respectively  inclined  at  equal  angles  to  the  adjacent  faces,  (fig.  32.) 
Truncation  and  bevelment  can  occur  only  on  edges  formed  by  the  meet- 
ing  ofequ*l  planes. 


36 


STRUCTURE    OF    MINERALS. 


2.  Half  the  similar  parts  of  a  crysial,  alternate  imposition, 
are  modified  independently  of  the  other  half. 

In  the  cube,  octahedron,  or  dodecahedron,  if  one  edge  is 
replaced,  all  the  other  edges  will  be  replaced,  and  by  the 
same  planes.  If  there  are  two  planes  on  one  edge,  (fig.  32} 
there  will  be  two  on  every  other  edge  ;  and  the  two  on  each 
will  have  the  same  inclinations.  If  there  are  three  planes 
on  one  angle,  (fig.  33)  there  will,  in  the  same  manner,  be 
three  on  the  other  seven  angles.  Perfect  symmetry  is  thus 
preserved,  however  numerous  the  added  planes.  The  fol- 
lowing figures  illustrate  this  principle,  that  all  the  edges,  and 
all  the  angles  are  modified  alike. 

32  33  34  35 


This  symmetry  is  well  seen  in  the  solids  which  the  secon- 
dary planes,  in  the  above  figures,  produce,  if  enlarged  till 
the  primary  planes  are  obliterated.  Thus  from  figure  32, 
comes  the  form  in  figure  36,  the  planes  e'  being  enlarged  till 
the  planes  P  are  obliterated  ;  from  33,  comes  the  form  in 
fig.  37 ;  from  34,  the  form  in  38  ;  and  from  35,  the  form  in 
39.  The  form  in  figure  37  has  24  faces,  and  is  called  a 
trapezohedron.  It  is  common  in  garnet  and  leucite. 
36  37  38  39 


In  figure  35,  there  are  six  planes  on  each  angle,  and  as  there 
are  eight  angles  in  the  cube,  the  solid  represented  in  figure 
39  has  forty-eight  faces.  Both  38  and  39  are  forms  of  the 
diamond. 

In  connection  with  the  law  above  given,  it  is  stated  that 
half  the  similar  parts  may  be  modified  independently  of 
the  other  half.  The  parts  thus  modified  are  alternate  with 
one  another  and  still  produce  symmetrical  solids.  Thus  the 

What  second  law  is  mentioned  ?     Explain  the  first  law  by  examples. 


MODIFICATIONS   OF   CRYSTALS. 


37 


cube  may  have  only  the  alternate  angles  replaced ;  or  only 
one  of  the  two  beveling  planes  shown  in  figure  32  may  occur 
on  each  edge  ;  or  three  of  the  six  on  each  angle  in  figure  35. 
The  following  are  examples  ;  and  each  figure  in  the  lower 
line,  represents  the  completed  form,  produced  by  extending 
the  secondary  planes  in  the  figure  above,  to  the  obliteration 
of  the  primaries,  as  explained  on  the  preceding  pages. 
40  41  42  43 


The  replacement  begun  in  figure  40,  continued  to  the  oblit- 
eration of  the  Ps,  produces  figure  44,  which  is  a  tetrahedron, 
or  three-sided  pyramid.  So  the  planes  a  in  figure  41,  give 
rise  to  fig.  45 ;  the  planes  e  in  42,  to  figure  46,  which  is  a 
pentagonal  dodecahedron,  so  called  because  it  has  twelve 
pentagonal  (or  five-sided)  faces.  The  forms  represented  in 
figures  40  and  41  are  common  in  boracite,  and  those  of  figures 
42,  43,  in  iron-pyrites.  These  forms  with  half  the  full  num- 
ber of  planes  are  called  hemihedral  forms,  from  the  Greek 
words  for  half  and  face. 

The  tetrahedron  is  sometimes  placed  among  the  primary 
forms  ;  but  it  is  properly  a  secondary  form,  derived  from  the 
cube,  in  the  manner  here  explained,  or  from  the  octahedron 
by  the  extension  of  four  faces  to  the  obliteration  of  the  other 
four.  (Compare  figs.  2  and  44.) 

In  the  right  square  prism,  the  basal  edges  being  unequal 
to  the  vertical,  (because  the  prism,  unlike  the  cube,  is  higher 
than  broad,)  these  two  kinds  of  edges  are  not  replaced  by 
similar  planes,  and  the  basal  may  be  modified  when  the 
lateral  are  not  modified,  (figs.  48,  49.)  The  lateral  edgei 
may  be  truncated,  because  their  including  planes  are  equal ; 

Explain  the  second  law.  What  are  the  resulting  forms  called  ? 
What  is  said  of  the  tetrahedron  ? 

4 


38 


STRUCTURE    OF   MINERALS. 


the  terminal  cannot  be  truncated,  lout  are  replaced  by  planes 

unequally  inclined  to  the  including  planes.     The  solid  angles 

48  49  50 


of  the  square  prism  are  of  one  kind  and  are  replaced  alike,  as- 
in  figures  23,  50  ;  all  the  angles  in  these  figures  have  the 
same  number  of  planes,  and  the  two  adjacent  planes  in  figure 
50  are  similar  in  their  inclinations,  because  the  lateral  planes 
M,  M,  of  a  square  prism,  are  equal. 

In  the  rectangular  and  rhombic  prisms  the  lateral  axes  are 
unequal.  Consequently  in  the  rectangular  prism,  two  basal 
edges  differ  from  the  other  two,  and  are  therefore  modi- 
fied independently  (figs.  51,  52.)  The  planes  e  extended  to 
the  obliteration  of  T  and  P,  would  produce  a  rhombic  prism 
(in  a  horizontal  position,)  as  shown  in  figure  53,  and  another 
horizontal  prism  may  be  formed  by  the  extension  of  the 
planes  e,  fig.  52.  In  the  rhombic  prism  the  basal  edges  cor- 
51  52  53  54 


respond  to  the  angles  of  the  rectangular  prism 
(see  fig.  26J)  and  are  similar  and  simultaneously 
replaced  as  in  figure  24.  The  basal  angles  are 
unlike,  one  being  obtuse  and  the  other  acute,  and 
the  planes  of  the  two  (fig.  54)  differ  in  their  in- 
clinations. The  lateral*  edges  differ  in  the  same 
manner,  two  being  obtuse  and  two  acute,  and  they  are  inde- 
pendently replaced,  as  in  figure  55.  The  two  planes  e  are 
similar  planes,  because,  in  a  rhombic  prism,  M  and  M  are 
equal ;  and  the  extension  of  these  planes  may  produce  another 
rhombic  prism. 

In  an  oblique  rhombic  prism  the  superior  basal  edges  dif- 

Explain   these   laws  from   the   square  prism ;   the  rectangular  and 
rhombic. 


MODIFICATIONS   OF    CRYSTALS. 


fer  from  the  inferior  in  front,  two  being  obtuse  and  two  acute  ; 
consequently,  they  are  independently  replaced.  Figure  56, 
shows  the  replacement  of  the  obtuse  basal.  So  also  the  front 
angles  differ  in  the  same  manner,  the  upper  (left  side  in  fig. 
57)  being  independent  <Df  the  inferior  in  its  modifications. 
56  57  58  59 


But  the  four  lateral  angles  are  similar  (fig.  58.)  Two  of  the 
lateral  edges  ure  obtuse  and  two  acute,  as  in  the  right  rhom- 
bic prism,  and  their  secondary  planes  are  therefore  unlike 
(fig.  59.) 

In  the  oblique  rhomboidal  prism, 
7-only  two  diagonally  opposite  edges 
or  angles  are  similar,  and  the  modi- 
fications of  one  edge  are  therefore 
independent  of  those  of  all  the  other 
edges,  except  the  one  diagonally; 
opposite  :  the  same  is  true  of  the 
angles-  The  difference  between  this  prism  and  the  oblique 
rhombic  will  thus  be  seen  on  comparing  figures  56  and  60, 
and  also  figures  58  and  61 : 

In  the  rhombohedron,  the  distinction  of  vertical  and  lateral 
solid  angles  has  already  been  explained,  and  also  the  differ- 
ence between  the  terminal  and  lateral  edges.  The  figures 
given  will  show  how  these  distinctions  are  carried  out  in  the 
63  64  «5 


modifications.  In  figure  62,  the  terminal  solid  angles  are 
replaced,  but  none  of  the  lateral.  In  figures  64,  65  and  29, 
the  lateral  angles  are  replaced,  but  not  the  terminal.  Figure 
63,  has  the  terminal  edges  replaced,  and  figures  68  and  28. 
the  lateral  edges. 

Expiain  the  laws  with  regard  to  secondary  planes  from  th6  oblique 
riioinbic  prism  ^  oblique  rhomboidal ;  the  rhombohedron. 


40 


STRUCTURE    OF   MINERALS. 


When  the  planes  a'  in  figure  64  are  a  little  more  extended, 

the  form  is  changed  to  figure  65,  or  a  double  six-sided  pyramid. 

It  is  in  this  way  that  the  pyramidal  form  of  crystals  of  quartz 

is  produced  from  the  primary  rhombohedron.     In  figure  66, 

66  67  63  69 


«',  as  is  seen,  is  a  different  plane  from  a"  in  figure  64.  By 
enlarging  the  planes  a',  till  the  planes  R  are  obliterated, 
figure  67  is  obtained,  an  acute  rhombohedron.  This  may 
appear  a  singular  result :  but  it  will  be  understood  on  con- 
sidering that  there  are  six  lateral  angles  ;  and  three  of  the 
planes  a'  incline  upward,  and  three,  alternate,  incline  down- 
ward ;  they  must  therefore  produce  an  oblong  solid,  bounded 
by  six  equal  faces,  which  is  nothing  else  than  a  rhombohedron. 
In  figure  68,  the  lateral  edges  are  beveled  by  the  planes  e*. 
The  planes  e  enlarged  to  the  obliteration  of  the  faces 
R,  lead  to  the  form  in  figure  69 — a  twelve -sided  figure,  or 
dodecahedron,  and  called  from  the  shape  of  its  faces,  a 
scalene  dodecahedron.  It  is  the  form  of  dog-tooth  spar,  a 
variety  of  calcareous  spar.  In  figures  28,  29,  the  planes  e 
and  a  are  each  parallel  to  the  vertical  axis,  and  they  con- 
sequently produce  prisms  when  extended,  as  explained  on 
pages  31,  32. 

In  figure  3,  under  Tourmaline,  we  have  an  instance  of  a 
Itemihedral  modification  in  the  hexagonal  system.  The  ex- 
tremities of  the  prism,  as  will  be  observed,  have  different 
secondary  planes,  there  being  in  addition  to  the  three  faces 
R,  three  small  triangular  planes  above,  and  three  narrow 
linear  planes  below.  Topaz  crystals  are  also  differently 
modified  at  the  extremities,  and  are  examples  of  hemihedral 
modifications  in  a  right  rhombic  prism. 

Another  law  gives  still  greater  interest  to  the  study  of 
crystallography :  but  it  can  only  be  briefly  alluded  to  in  this 
place.  When  speaking  of  the  right  square  prism  it  was 

Mention  some  instances  of  hemihedral  modifications,  and  explain. 


MODIFICATION    OF    CRYSTALS. 


41 


r 


stated  that  the  basal  edges  were  never  truncated,  but,  when 
modified,  were  replaced  by  planes  unequally  inclined  to  the 
basal  and  lateral  faces  of  the  primary.  These  secondary 
planes  do  not  however  occur  at  random,  at  any  possible  in- 
clination ;  but  there  is  a  direct  relation,  in  all  instances,  to 
the  comparative  neight  and  breadth  of  the  fundamental  form 
of  the  mineral.  The  same  is  true  of  planes  on  the  angles, 
and  in  secondaries  to  all  the  fundamental  forma. 

Take  a  cube  and  cut  off  evenly  one  of  the  edges  :  this 
removes  parts  of  two  other  edges,  at  each  end  of  the  plane. 
It  is  found  that  in  cubic  crystals  these  parts  are  either  equal 
to  one  another,  or  one  is  double  of  the  other,  or  treble  ;  or 
iii  some  other  simple  ratio.  The  same  is  true  in  the  other 
fundamental  forms,  except  that,  as  stated,  the  relative  height 
and  breadth  of  the  prism  come  into  account,  and  influence 
the  result. 

For  example  :  in  figure  70,  70  71 

(a  section  of  a  cube,)  P  M  and  y  .">.'>-  ir 
P  N  are  equal  edges,  divided 
into  equal  parts  ;  now  a  plane  * 
on  an  edge  of  a  cube,  as  a  btft 
removes,  as  is  seen,  equal  parts 
of  P  M  and  P  N  ;  another,  as  \ 
a  c,  removes  twice  as  many  parts  of  one 
edge  as  of  the  other ;  and  so  other  planes  have  like  simple 
ratios.  In  figure  71,  a  section  of  a  prism,  the  lines  P  M  and 
Ti^Wtotd^jhd  breadth  of  the  prism)  are  unequal :  let  them 
be  dlvKBH^lHike  number  of  parts ;  then  a  plane  on  an 
edge>jas  a%&V;wiilvcut  off  as  many  parts  of  P  M  as  of  P  N ; 
others,  as  a  c,  b  d,  twice  as  many  parts  of  one  as  the  other : 
and  so  on.  a  ^truncates  the  edge  in  figure  70  ;  but  not  so 
in  figure  71.  It  is  evident  to  the  mathematical  scholar  that 
the  inclination  of  a  plane  a  b  to  P  N  or  P  M,  is  sufficient  to 
determine  the  relative  dimensions  of  P  a  and  P  i,  or  the  rela- 
tive height  and  breadth  of  the  fundamental  form. 

These  principles  give  a  mathematical  basis  to  the 
science. 

Thus  we  perceive  that  the  attraction  which  guides  each 
particle  to  its  place  in  crystallization,  produces  forms  of 
Mathematical  exactness.  It  covers  the  crystal  with  scores 
»f  facets  of  finished  brilliancy  and  perfection ;  and  these 

What  other  law  is  there,  respecting  the  occurrence  of  secondary 
planes  1  Explain  by  the  figures. 

4* 


STRUCTURE    OF  MINERALS. 


facets  are  not  only  uniform  in  number  on  similar  parts  of  a 
crystal,  but  are  even  fixed  in  every  angle  and  every  edge.* 


COMPOUND    CRYSTALS. 


In  the  preceding  pages,  we  have  been  considering  simple 

crystals,  and  their  secondary  forms.     The  same  forms  are 

occasionally  compounded  so  as  to  make  what  have  been 

called  twin  or  compound  crystals.    They  will  be  understood 

72  73  74  75 


at  once  from  the  annexed  figures.     Figure  72  represents  a 
crystal  of  snow  of  not  unfrequent  occurrence.     It  consists,  as 

What  is  a  twin  or  compound  crystal  1 

*  On  a  preceding  page,  it  has  been  explained  that  in  monometric  cys- 
tals  the  axes  are  equal  ;  in  dimetric  and  hexagonal  crystals  the  lateral 
axes  are  equal,  and  the  vertical  is  of  a  different  length,  shorter  or  longer. 
In  the  other  systems,  the  trimetric  and  the  two  oblique  systems,  the 
three  axes  are  all  unequal.  In  the  above  paragraphs  it  has  been  shown 
that  the  relative  lengths  of  the  axes  in  a  fundamental  form  of  a  crystal 
are  fixed,  and  may  be  determined  by  simple  calculations.  These  fixed 
relative  dimensions  are  supposed  to  be  the  relative,  dimensions  of"  thp 
particles  or  molecules  constituting  crystals  ;  that  is  if  -hr- 
form  of  a  crystal  is  twice  as  long  as  broad,  the  saSl^Hi^^ratsmole- 
eules.  The  molecules  of  a  cube  must  therefore  be  equal  in  different 
directions,.;  those  of  a  square  prism  must  be  longer -or  shorter  than 
broad,  but  equal  in  breadth  and  thicknesss  ;  those  of  a  rectangular  prism 

must  be  unequal  in  three 
directions  ;  and  the  relative 
inequality  is  determinable  as 
just  stated.  The  simplest  and 
most  probable  view  of  the 
forms  of  molecules  is  that  they 

^^^  are   spheres  for  monometric 

solids ;  and  ellipsoids  of  different  axes  for  the  other  forms.     Figure  1 
represents  a  sphere. 

Figure  2  represents  an  ellipsoid  with  the  lateral  axes  equal,  as  seen 
in  the  cross  section  2a  ;  it  is  the  form  in  the  dimetric  and  hexagonal 
systems. 

Figure  3  represents  an  ellipsoid  with  the  lateral  axes  unequal  (fig.  3a), 
as  in  the  trimetric  and  oblique  systems  ;  a  variation  in  the  length  of  the 
axes  will  vary  the  dimensions,  according  to  any  particular  case. 


COMPOUND    CRYSTALS. 


43 


77 


is  evident  to  the  eye,  either  of  six  crystals  meeting  in  a  point, 
or  of  three  crystals  crossing  one  another.  Besides,  there 
are  numerous  minute  crystals  regularly  arranged  along  the 
rays.  Figure  73  represents  a  cross  (cruciform)  crystal  of 
staurotide,  which  is  similarly  compound,  but  made  up  of 
fewer  crystals.  Figure  74,  is  a  compound  crystal  of  gypsum, 
and  figure  75,  one  of  spinel.  These  will  be  understood  from 
the  following  figures. 

Figure  76  is  a  simple  crystal  of  gyp- 
sum ;  if  it  be  bisected  along  a  ft,  and 
the  right  half  be  inverted  and  applied 
to  the  other,  it  will  form  figure  74, 
which  is  therefore  a  twin  crystal,  in 
which  one  half  has  a  reverse  position 
from  the  other.  Figure  77,  is  a  simple 
octahedron  ;  if  it  be  bisected  through  w 
the  dotted  line,  and  the  upper  half,  after  being  revolved  half 
way  around,  be  then  united  to  the  lower,  it  produces  figure 
75.  Both  of  these  therefore  are  similar  twins,  in  which  one 
of  the  two  component  parts  is  reversed  in  position.*  Com- 
pound crystals  are  generally  distinguished  by  their  re&ntering 
angles. 

Besides  the  above,  there  are  also  geniculated  crystals,  as 
in  the  annexed  figure.  The  bending  has  here  78 

taken  place  at  equal  distances  from  the  center 
of  the  crystal  ;  and  it  must  therefore  have 
been  subsequent  in  time  to  the  commence- 
ment of  the  crystal.  The  prism  began  from 
a  simple  molecule  :  but  after  attaining  a  certain 
length,  an  abrupt  change  of  direction  took  place.  The  angle 
of  geniculation  is  constant  in  the  same  mineral  species  ;  for 
the  same  reason  that  the  angles  of  secondary  planes  are 
fixed  ;  and  it  is  such  that  a  cross  section  directly  through  the 
geniculation  is  parallel  to  the  position  of  a  common  secon- 
dary plane.  In  the  figure  given,  the  plane  of  geniculation  is 
parallel  to  one  of  the  terminal  edges. 

Mention  illustrations.  Explain  their  structure  in  the  case  of  gypsum 
and  spinel.  What  is  said  of  geniculated  crystals'? 

*  Such  crystals  have  proceeded  from  a  compound  nucleus  in  which  one 
of  the  two  particles  was  reversed.  Compound  crystals  of  the  kind 
above  described,  thus  differ  from  simple  crystals  in  having  been  formed 
from  a  nucleus  of  two  or  more  united  molecules,  instead  of  from  a  simple 
nucleus. 


44  STRUCTURE    OF   MINERALS. 

DIMORPHISM. POLYMORPHISM. 

It  was  formerly  supposed  that  the  same  chemical  com- 
pound could  have  but  a  single  mode  of  crystallization.  But 
later  researches  have  discovered  that  there  are  many  in- 
stances of  substances  crystallizing  according  to  two  distinct 
systems.  Thus  sulphur  at  different  times  crystallizes  in  ob- 
lique prisms  and  right  rhombic  octahedrons,  or  according  to 
the  two  systems  monoclinate  and  trimetric.  Carbonate  of 
lime  at  one  time  takes  on  the  rhombohedral  form,  and  is 
then  called  calc  spar ;  at  another,  that  of  a  rhombic  prism, 
and  it  is  then  termed  arragonite.  Again,  sulphuret  of  iron 
presents  us  both  with  cubical  (monometric)  crystals  and 
rhombic  prisms  (trimetric.)  As  far  as  investigation  has  gone, 
it  has  appeared  that  one  of  these  forms  is  assumed  at  a  lower 
temperature  than  the  other ;  and  this  takes  place  uniformly, 
so  that  the  temperature  attending  solidification,  in  certain 
cases  at  least,  determines  the  forms  and  system  of  crystal- 
lization. How  far  other  causes  operate  is  unknown. 

This  property  is  termed  dimorphism,  (from  the  Greek  dis, 
two  or  twice,  and  morphe,  form,)  and  a  substance  presenting 
two  systems  of  crystallization  is  said  to  be  dimorphous.  In 
addition  to  the  above,  garnet  and  idocrase,  the  one  dodeca- 
hedral,  and  the  other  square-prismatic,  are  different  forms 
of  the  same  substance.  Rutile,  which  is  dimetric,  anatase, 
dimetric  also,  but  of  different  dimensions,  and  Brookite,  which 
is  trimetric,  are  three  distinct  forms  of  the  same  substance," 
oxyd  of  titanium.  In  this  last  case,  the  property  has  been 
called  trimorphism,  (from  the  Greek  tris,  three  times,  and 
morphe,  form.)  As  the  number  of  forms  may  be  still  greater, 
the  more  general  term  polymorphism  (polus,  many,  and 
morphe)  has  been  introduced  to  include  all  cases,  whatever 
the  number  of  forms  assumed. 

A  polymorphous  substance  in  its  different  states  presents 
not  merely  difference  of  form.  There  is  also  a  difference  in 
hardness,  specific  gravity  and  luster,  in  fact,  in  nearly  all 
physical  qualities.  Arragonite  has  the  specific  gravity  2'93, 
and  calc  spar  only  2'7  ;  the  hardness  of  arragonite  is  3£, 
and  that  of  calc  spar  but  3. 

May  the  same  substance  crystallize  under  more  than  one  fundamen- 
tal form  "?  -Mention  examples.  What  is  this  property  called  1  What 
is  said  of  oxyd  of  Titanium  1  What  is  trimorphism  1  polymorphism  1 
What  other  differences  beside  that  of  form  are  connected  with  poly- 
morphism 1 


IRREGULARITIES    OF    CRYSTALS. 


45 


The  forms  of  a  dimorphous  substance  differ  in  stability. 
Arragonite  when  heated  gently  falls  to  powder,  arising  from 
a  change  in  the  condition  of  its  particles.  Arragonite  has 
been  obtained  by  evaporating  a  solution  of  lime  over  a  water 
bath,  and  calc  spar  when  the  same  was  evaporated  at  the  ordi- 
nary temperature.  When  a  right  rhombic  prism  of  sulphate 
of  zinc  (which  is  dimorphous)  is  heated  to  126°  F.  certain 
points  in  its  surface  become  opaque,  and  from  these  points, 
bunches  of  crystals  shoot  forth  in  the  interior  of  the  speci- 
men ;  and  in  a  short  time  the  whole  is  converted  into  an 
aggregate  of  these  crystals,  diverging  from  several  centers  on 
the  surface  of  the  original  crystal.  These  small  crystals 
are  oblique  rhombic  prisms  ;  and  the  same  form  may  be  ob- 
tained by  evaporating  a  solution  at  this  temperature  or  above 
it.  Many  other  similar  cases  might  be  cited,  but  these  serve 
to  explain  the  principle  in  view. 


IRREGULARITIES    OF    CRYSTALS. 

Before  concluding  this  subject,  a  few  remarks  may  be 
added  on  the  irregularities  of  crystals. 

Crystals  of  the  same  form  vary  much  in  length,  and  in  the 
size  of  corresponding  faces.  The  same  mineral  may  occur 
in  very  short  prisms,  or  in  long  and  slender  prisms  :  and 
some  planes  may  be  so  enlarged  as  to  obliterate  others  ; 
a  few  figures  of  quartz  crystals  will  illustrate  these  pecu- 
liarities. 

79  80  81  82 


Figure  79  is  the  regular  form  of  the  crystal.  Figure  80  is 
the  same  form  with  some  faces  very  much  enlarged,  and 
others  very  small.  Figure  81  is  a  very  short  prisrn  and 
pyramid  of  quartz,  such  as  is  often  seen  attached  to  the 
surface  of  rocks ;  and  figure  82  is  a  similar  form  .very  much 
elongated.  Notwithstanding  all  these  variations,  every  angle 

What  are  some  of  the  irregularities  of  crystals? 


46 


STRUCTURE    OF    MINERALS. 


of  inclination  remains  the  same  :  and  this  is  a  general  fact 
in  all  crystals,  that  whatever  distortions  take  place,  the  angles 
are  constant.  Greater  diversity  is  given  to  the  shapes  of 
crystals  by  these  simple  variations,  without  multiplying  the 
number  of  distinct  forms.  'Figure  83  is  a  tapering  prism  of 
the  same  mineral,  with  a  minute  pyramid  at  the  apex.  The 
faces  'of  this  pyramid  have  exactly  the  same  inclinations  as 
those  of  figure  79. 

The  constancy  of  the  angles  shows  that  the  fundamental 
form  of  the  crystal,  or,  in  other  words,  the  form  of  its  mole- 
cules, is  constant,  amid  all  these  variations  of  size  and  shape. 

Crystals  have  sometimes  curved  faces.  The  faces  of 
diamonds  are  usually  convex,  and  some  crystals  are  almost 

84  spheres.     Figure  84  is   one  of  these  diamond 
crystals.     It  is  the  same  form  as  is  represented 
in  figure  45.     For  cutting   glass,  they  always 
select  those  crystals  that  have  a  natural  curved 
edge,  as  others  are  much  inferior  for  the  purpose 
and  sooner  wear  out.     In  figure  85  a  different 

kind  of  curvature  is  represented.     It  is  a  curved  rhombohe- 

85  dron,  in  which  the  opposite  faces  are  parallel  in 
their  curving  :  it  is  a  common  form  of  spathic  iron 

tnd  pearl  spar.     The  latter  mineral  from  Lock- 
port,  New  York,  is  always  curved  in  this  way. 

Si  ill  more  singular  curvatures  are  sometimes 
met  with.  In  the  mammoth  cave  of  Kentucky, 
leaves,  vines  and  flowers  are  beautifully  imita- 
ted in  alabaster.  Some  of  the  "  rosettes"  are 
a  foot  in  diameter,  and  consist  of  curving  leaves, 
clustered  in  graceful  shapes.  The  frostings  on 
our  windows  in  winter  are  often  miniature  pic- 
.tures  of  forests  and  vines  with  rolled  tendrils. 
I  It  is  one  among  the  many  singular  results  of 
k crystallization.  On  the  cool  mornings  of  spring 
;or  autumn,  in  this  climate,  twigs  of  plants  are 
I  occasionally  found  encircled  by  fibrous  icy 
curls,  (fig.  86,)  which  are  attached  vertically  to 
the  stem.  They  are  formed  during  the  night, 
and  disappear  soon  after  the  appearance  of  the 
sun. 


What  is  said  of  curved  crystals  ? 
gypsum  ?  of  ice  ? 


What  of  curved  crystallizations  of 


MEASUREMENT    OF    CRYSTALS. 


47 


ON    MEASURING    ANGLES    OF    CRYSTALS. 

As  the  angles  of  crystals  are  constant,  minerals,  as  has 
been  stated,  may  often  be  distinguished  by  measuring  these 
angles.  This  is  done  by  means  of  instruments  called  goni- 
ometers, a  term  meaning,  literally,  angle-measurers.*  These 
are  of  two  kinds  ;  one  is  called  the  common  goniometer,  the 
other  the  reflecting  goniometer. 

The  common  goniometer  depends  on  the  87 

very  simple  principle  that  when  two  straight 
lines  cross  one  another,  as  A  E,  C  D  in  the 
annexed  figure   87,  the  parts  will  diverge 
equally  on  opposite  sides  of  the  point  of  in-  °' 
tersection  (O)  ;  that  is,  in  mathematical  language,  the  angle 
A  O  D  is  equal  to  the  angle  C  O  E,  and  A  O  C  is  equal  to  D  O  E. 

The  instrument  in  common  use  is  here  represented. 


It  consists  of  two  arms,  a  &,  c  d,  moving  on  a  pivot  at  o :  the  arms 
open  and  shut,  and  their  divergence,  or  the  angle  they  make 
with  one  another,  is  read  off  on  the  graduated  arc  attached. 
In  using  it,  press  up  between  them,  the  edge  of  the  crystal 
whose  angle  is  to  be  measured,  and  continue  opening  the  arms 
thus  till  the  inner  edges  lie  evenly  against  the  faces  that  include 

How  are  the  angles  of  crystals  measured?  Explain  the  principle  of 
the  common  goniometer  from  the  figure.  Explain  the  common  goni- 
ometer and  its  use. 

*  From  the  Greek  gonu,  angle,  and  meiron,  measure. 


48  STRUCTURE  OF  MINERALS. 

the  required  angle.  To  insure  accuracy  in  this  respect,  hold 
the  instrument  and  crystal  between  the  eye  and  the  light, 
and  observe  that  no  light  passes  between  the  arm  and  the 
applied  faces  of  the  crystal.  The  arms  may  then  be  secured 
in  position  by  tightening  the  screw  at  o  ;  the  angle  will  then 
be  measured  by  the  distance  on  the  arc  from  k  to  the  left 
or  outer  edge  of  the  arm  c  d,  this  edge  being  in  the  line  of 
o,  the  center  of  motion.  As  the  instrument  stands  in  the 
figure,  it  reads  45°.  The  arms  have  slits  at  g  h,  n  p,  by 
which  they  may  be  shortened  so  as  to  make  them  more  con- 
venient for  measuring  small  crystals. 

In  some  instruments  of  this  kind  the  arc  is  detached  from 
the  arms.  When  this  is  the  case,  after  the  measurement  is 
made  and  the  screw  at  o  tightened,  the  arc  (which  has  the 
shape  ofafb  in  the  annexed  figure,  except  that  from  a  to  b 
is  a  solid  bar)  is  adjusted  to  the  upper  edge  of  one  of  the 
arms,  bringing  the  mark  at  o,  the  center,  exactly  to  the  center  of 
divergence  of  the  arms.  The  angle  is  then  read  off  as  before. 

With  a  little  ingenuity  the  student  may  construct  a  goni- 
ometer for  himself  that  will  answer  a  good  purpose.  A  semi- 
circle may  be  described  on  mica  or  a  glazed  card,  of  the 
shape  in  figure  88  :  it  should  then  be  divided  into  halves  at 
y,  and  again  each  half  subdivided  into  nine  equal  parts. 
Each  of  these  parts  measures  10  degrees  ;  and  if  they  are 
next  divided  into  ten  equal  parts,  each  of  these  small  divisions 
will  be  degrees.  The  semi-circle  may  then  be  cut  out,  and 
is  ready  for  use.  The  arms  might  also  be  made  of  stiff  card 
for  temporary  use  ;  but  mica,  bone  or  metal  is  better.  The 
arms  should  have  the  edges  straight  and  accurately  parallel, 
and  be  pivoted  together.  The  instrument  may  be  used  like 
that  last  described,  and  \vill  give  approximate  results,  suffi- 
ciently near  for  distinguishing  most  minerals.  The  ivory 
rule  accompanying  boxes  of  mathematical  instruments,  having 
upon  it  a  scale  of  sines  for  measuring  angles,  will  answer 
an  excellent  purpose,  and  is  as  con-  89 

venient  as  the  arc.  The  annexed 
figure  will  illustrate  the  mode  of 
using  it.  The  scale  is  graduated 
along  the  margin,  the  middle  point 
marking  90°,  and  the  divisions 
either  side  10  degrees  (as  in  the  figure)  and  also  single  de- 
How  is  it  used  when  the  arms  are  detached  1  How  may  a  temporary 
goniometer  be  made  ?  How  may  a  scale  of  sines  be  used  ? 


MEASUREMENT    OF    CRYSTALS.  49 

grees.  The  arms  are  so  applied  to  the  scale,  that  the  center 
of  motion  is  exactly  at  the  extremity  of  the  middle  line, 
marked  90 ;  and  the  leg  crossing  the  scale  (or  that  edge  of  it 
in  the  line  of  the  center  of  motion)  will  then  indicate  by  its 
position  over  the  graduated  margin,  the  angle  desired.* 

In  making  such  measurements  it  is  important  to  remember 
that — 

1.  An  angle  A  O  D  (figure  87)  and  A  O  C,  together, 
equal  180°  ;  so  that  if  A  O  C  be  measured,  A  O  D  is  ascer- 
tained by  subtracting  A  O  C  from  180°. 

2.  In  a  rhomb  or  rhomboid,  b  a  b  and  a  b  a,  to- 
gether, equal  180° ;  and  one  may  be  ascertained 
by  subtracting  the  other  from  180°.     If  an  obtuse 
angle  of  a  rhombic  prism  has  been  measured  and 

found  to  be  110°,  and  the  acute  angle  on  measurement  is  as- 
certained to  be  60°,  the  student  should  add  the  two  together 
to  find  whether  the  sum  is  180°  ;  for  if  not,  there  is  some 
error  in  the  measurement^  and  it  should  be  repeated.  IIO^ 
added  to  60°  makes  170 J,  showing  in  this  case  an  error 
of  10°. 

3.  In  any  polygon,  the  sum  of  the  angles  is  equal  to  twice 
as  many  right  angles  as  there  are  sides  less  two.     Let  the 
number  of  sides,  for  example,  be  6  :  6  less  two  is  4 ;  and 
tfie  angles  together  equal  twice  4,  (or  8,)  right  angles,  which 
is  equivalent  to  8  X  90°  =720°.     If  we  have  a  prism  of  six 
sides,  and  wish  to  ascertain  the  angles  between  these  sides, 
the  angles  should  be  measured  successively,  and  the  whole 
added  together  to  ascertain  whether  the  measurements  are 
correct.     If  the  sum  is  720°,  there  is  good  reason  to  confide 
in  them.     Crystals  are  at  times  a  little  irregular ;  and  this 
should  be  looked  to,  as  part  of  the  apparent  error  may  at 
times  be  thus  accounted  for.     This  general  principle  and  the 


What  three  points  must  be  observed  in  making  measurements  ? 

*  Another  mode  for  approximate  results  consists  in  holding  the  crys- 
tal with  the  two  faces  (whose  inclination  is  to  be  measured)  in  an 
exactly  vertical  position  over  a  piece  of  paper  :  then  place  a  small  rule 
parallel,  as  near  as  the  eye  can  judge,  to  one  face,  and  draw  a  line  ;  next 
do  the  same  for  the  other  face.  The  angle  between  the  two  lines, 
measured  either  by  an  arc  or  the  ivory  rule  just  mentioned,  is  the 
desired  inclination.  With  practice,  much  skill  may  be  acquired  in 
such  trials.  They  may  be  made  with  microscopic  crystals  under  a 
microscope. 


50 


STRUCTURE    OF    MINERALS. 


preceding,  which  is  only  a  simpler  case  of  the  same,  are  of 
great  importance  in  the  measurements  of  crystals. 

Reflecting  Goniometer.  The  reflecting  goniometer  affords 
a  more  accurate  method  of  measuring  crystals  that  have 
luster,  and  may  be  used  with  those  of  minute  size.  The 
principle  on  which  this  instrument  is  constructed  will  be  un- 
derstood from  the  annexed  figure  (fig.  90)  representing  a 
crystal,  whose  angle  a  b  c  is  required. 
The  eye,  looking  at  the  face  of  the 
crystal  b  c,  observes  a  reflected  image 
of  m,  in  the  direction  P  n.  On  revolving, 
the  crystal  till  a  b  has  the  position  of 
b  c,  the  same  image  will  be  seen  again  in 
the  same  direction  P  n.  As  the  crystal 
is  turned,  in  this  revolution,  till  a  b  d  has  the  present  position 
of  b  c,  the  angle  d  b  c  measures  the  number  of  degrees 
through  which  it  is  revolved.  But  d  b  c,  subtracted  from 
180°,  equals  the  angle  of  the  crystal  a  b  c.  The  crystal  is 
therefore  passed  in  its  revolution  through  a  number  of  de- 
grees, which,  subtracted  from  180°,  give  the  required  angle. 
This  angle,  in  the  reflecting  goniometer  of  Wollaston,  is 
measured  by  attaching  the  crystal  to  a  graduated  circle  which 
revolves  with  it,  as  here  represented  (fig.  91.) 

A  B  is  the  graduated  cir- 
cle. The  wheel,  m,  is  at- 
tached to  the  main  axis,  and 
moves  the  graduated  circle 
together  with  the  adjusted 
crystal.  The  wheel,  n,  is 
*  connected  with  an  axis 
which  passes  through  the 
main  axis,  (which  is  hollow 
for  the  purpose,)  and  moves 
merely  the  parts  to  which 
the  crystal  is  attached,  in 
order  to  assist  in  its  adjust, 
ment.  The  contrivances  for 
the  adjustment  of  the  crystal 
are  at  p,  q,  r,  s.  To  use  the  instrument,  it  must  be  placed  on 
a  small  stand  or  a  table,  and  so  elevated  as  to  allow  the  ob- 
server to  rest  his  elbows  on  the  table.  The  whole,  thus 


Explain  the  principle  of  the  reflecting  goniometer, 
of  using  the  instrument. 


Explain  the  mode 


MEASUREMENT    OF    CRYSTALS.  51 

firmly  arranged,  is  to  be  placed  in  front  of  a  window,  distant 
from  the  same  from  six  to  twelve  feet,  and  with  the  axis  of 
the  instrument  parallel  to  it.  Preparatory  to  operation,  a 
dark  line  must  be  drawn  below  the  window  near  the  floor, 
parallel  to  the  bars  of  the  window ;  or,  what  is  better,  on  a 
slate  or  board  placed  before  the  observer  on  the  table. 

The  crystal  is  attached  to  the  movable  plate,  ^,  by  a  piece 
of  wax,  and  so  arranged  that  the  edge  of  intersection  of  the 
two  planes  forming  the  required  angle,  shall  be  in  a  line  with 
the  axis  of  the  instrument.  This  is  done  by  varying  its 
situation  on  the  plate,  £,  or  the  situation  of  the  plate  itself,  or 
by  means  of  the  adjacent  joints  and  wheel,  r,  s,  p,  as  will  be 
readily  understood  from  the  instrument. 

When  apparently  adjusted,  the  eye  must  be  brought  close 
to  the  crystal,  nearly  in  contact  with  it,  and  on  looking  into 
a  face,  part  of  the  window  will  be  seen  reflected,  one  bar  of 
which  must  be  selected  for  the  trial.  If  the  crystal  is  cor- 
rectly adjusted,  the  selected  bar  will  appear  horizontal,  and 
on  turning  the  wheel,  n,  till  this  bar,  as  reflected,  is  observed 
to  approach  the  dark  line  below,  seen  in  a  direct  view,  it  will 
be  found  to  be  parallel  to  this  dark  line,  and  ultimately  to 
coincide  with  it.  If  there  is  not  a  perfect  coincidence,  the 
adjustment  must  be  altered  until  this  coincidence  is  obtained. 
Continue  then  the  revolution  of  the  wheel,  n,  till  the  same 
bar  is  seen  by  reflection  in  the  next  face,  and  if  here  there 
is  also  a  coincidence  of  the  reflected  bar  with  the  dark  line 
seen  direct,  the  adjustment  is  complete  ;  if  not,  alterations 
must  be  made,  and  the  first  face  again  tried.  A  few  succes- 
sive trials  of  the  faces,  will  enable  one  to  obtain  a  perfect 
adjustment. 

The  circle  A  B  is  usually  graduated  to  half  degrees,  and 
by  means  of  the  vernier,  t>,  minutes  are  measured.  After 
adjustment,  180 D  on  the  arc  must  be  brought  opposite  0,  on 
the  vernier.  The  coincidence  of  the  bar  and  dark  line  is 
then  to  be  obtained,  by  turning  the  wheel,  n.  When  ob- 
tained, the  wheel,  m,  should  be  turned  until  the  same  coinci- 
dence is  observed,  by  means  of  the  next  face  of  the  crystal. 
If  a  line  on  the  graduated  circle  now  corresponds  with  0  on 
the  vernier,  the  angle  is  immediately  determined  by  the 
number  of  degrees  opposite  this  line.  If  no  line  corresponds 
with  0,  we  must  observe  which  line  on  the  vernier  coincides 
with  one  on  the  circle.  If  it  is  the  18th  on  the  vernier,  and 
the  line  on  the  circle  next  below  0  on  the  vernier  marks  125°, 


52  STRUCTURE  OF  MINERALS. 

the  required  angle  is  121°  18' ;  if  this  line  marks  125°  30', 
the  required  angle  is  125°  48'. 

Some  goniometers  are  furnished  with  a  small  polished  re- 
flector, attached  to  the  foot  of  the  instrument  below  the  part 
s,  q,  which  is  placed  at  an  oblique  angle  so  as  to  reflect  a  bar 
of  the  window.  The  reflected  bar  then  answers  the  purpose 
of  the  line  drawn  below  the  window,  (or  on  a  slate,)  and  is 
more  conveniently  used. 

Other  modes  of  adjustment  for  the  crystal,  are  also  used  ; 
but  they  will  explain  themselves  to  the  student  acquainted 
with  the  above  explanations,  and  need  not  here  be  dwelt 
upon. 

MASSIVE    MINERALS,    OR    IMPERFECT    CRYSTALLIZATIONS. 

Massive  or  imperfectly  crystallized  minerals  either  consist 
of  fibers  or  minute  columns,  of  leaves  or  laminae,  or  of  grains : 
in  the  fast,  the  structure  is  said  to  be  columnar ;  in  the 
second,  lamellar ;  in  the  third,  granular.  We  have  a  familiar 
example  of  the  lamellar  structure  in  slate  rocks  and  many 
minerals  that  occur  in  masses  made  up  of  separable  laminae. 
The  fibrous  or  columnar  structure  is  common  in  seams  of 
rocks,  and  sometimes  in  incrustations  covering  exposed  sur- 
faces ;  the  material  of  the  seam  or  crust  is  made  up  of  mi- 
nute fibers  or  prisms  closely  compacted  together,  produced 
by  a  rapid  crystallization  on  the  supporting  surface.  The 
granular  structure  is  well  seen  in  loaf  sugar  and  statuary 
marble. 

1.  COLUMNAR  STRUCTURE.  The  following  are  explana- 
tions of  the  terms  used  in  describing  the  different  kinds  of 
columnar  structure. 

Fibrous ;  when  the  columns  are  minute  and  lie  in  the 
same  direction  ;  as  gypsum  and  asbestus.  Fibrous  minerals 
very  commonly  have  a  silky  luster :  a  fibrous  variety  of 
gypsum,  and  one  of  calc  spar,  have  this  luster  very  strongly, 
and  each  is  often  called  satin  spar. 

Reticulated  ;  when  the  fibers,  or  columns,  cross  in  various 
directions,  and  produce  an  appearance  having  some  resem- 
blance to  a  net. 

Stellated  ;  when  they  radiate  from  a  center  in  all  direc- 
tions, and  produce  a  star-like  appearance.  Ex.  stilbite, 
gypsum. 

What  kinds  of  structure  exist  in  massive  minerals  ]  Explain  the  dif- 
ferent varieties  of  columnar  structure,  fibrous;  reticulated,  &c. 


IMPERFECT    CRYSTALLIZATIONS.  53 

Radiated,  divergent  ;  when  the  crystals  radiate  from  a 
center,  without  producing  stellar  forms.  Ex.  quartz,  gray 
antimony. 

2.  LAMELLAR  STRUCTURE.     In  the  lamellar  structure,  the 
laminae  or  leaves  may  be  thick,  or  very  thin ;  they  some- 
times separate  easily,  and  sometimes  with  great  difficulty. 

When  the  laminae  are  thin  and  separate  easily,  the  struc- 
ture is  said  to  be  foliaceous.  Mica  is  a  striking  example, 
and  the  term  micaceous  is  often  used  to  describe  this 
structure. 

When  the  laminae  are  thick,  the  term  tabular  is  often  ap- 
plied ;  quartz  and  heavy  spar  afford  examples. 

The  laminae  may  be  elastic,  as  in  mica.,  flexible,  as  in  talc 
or  graphite,  or  brittle,  as  in  diallage. 

Small  laminae  are  sometimes  arranged  in  stellar  ghapes  ; 
this  occurs  in  mica. 

3.  GRANULAR   STRUCTURE.     When   the   grains   in  the 
texture  of  a  mineral  are  coarse,  it  is  said  to  be  coarsely  gran- 
ular, as  in  granular  marble  ;  when  fine,  finely  granular,  as 
in  granular  quartz ;  and  if  no  grains  can  be  detected  with 
the   eye,  the   structure  is   described  as  impalpable,  as  in 
chalcedony. 

Granular  minerals,  when  easily  crumbled  by  the  fingers, 
are  said  to  be  friable. 

IMITATIVE  SHAPES. — Massive  minerals  also  take  certain 
imitative  shapes,  not  peculiar  to  cither  of  these  varieties  of 
structure.  The  following  terms  are  used  in  describing  imi- 
tative forms : 

Globular;  when  the  shape  is  spherical  or  nearly  so :  the 
structure  may  be  columnar  and  radiating,  or  it  may  be  con- 
centric, consisting  of  coats  like  an  onion.  When  they  are 
attached,  they  are  called  implanted  globules. 

Eeniform  ;  kidney-shaped.  In  structure,  they  are  like 
globular  shapes. 

Botryoida,L  ;  when  a  surface  consists  of  a  group  of  rounded 
prominences.  The  prominences  or  globules  usually  consist 
of  fibers  radiating  from  the  center. 

Mammillary  ;  resembling  the  botryoidal,  but  consisting  of 
larger  prominences. 

Filiform  ;  like  a  thread. 

Acicular  ;  slender  like  a  needle. 

Explain  the  varieties  of  lamellar  structure  ;  of  granular  structure  ;  the 
several  imitative  shapes,  globular  ;  reniform,  &c. 
5* 


54  STRUCTURE  OF  MINERALS. 

Stalactitic  ;  having  the  form  of  a  cylinder,  or  cone,  hang- 
ing from  the  roofs  of  cavities  or  caves.  The  term  stalactite 
is  usually  restricted  to  the  cylinders  of  carbonate  of  lime 
hanging  from  the  roofs  of  caverns :  but  other  minerals  are 
said  to  have  a  stalactitic  form  when  resembling  these  in  their 
general  shape  and  origin.  Chalcedony  and  brown  iron  ore 
are  often  stalactitic. 

Reticulated ;  net-like. 

Drusy  ;  a  surface  is  said  to  be  drusy  when  covered  with 
minute  crystals. 

Amorphous  ;  having  no  regular  structure  or  form,  either 
crystalline  or  imitative.  The  word  is  from  the  Greek,  and 
means  without  shape. 

PSEUDOMORPHOUS    CRYSTALS. 

A  pseudomorphous*  crystal  is  one  that  has  a  form  which  is 
foreign  to  the  species  to  which  the  substance  belongs. 

Crystals  sometimes  undergo  a  change  of  composition  from 
aqueous  or  some  other  agency,  without  losing  their  form  ; 
for  example,  octahedrons  of  spinel  change  to  steatite,  still 
retaining  the  octahedral  form.  Cubes  of  pyrites  are  changed 
to  red  or  brown  iron  ore. 

Again :  crystals  are  sometimes  removed  entirely,  and  at  the 
same  time  and  with  equal  progress,  another  mineral  is  sub- 
stituted ;  for  example,  when  cubes  of  fluor  spar  are  trans- 
formed to  quartz.  The  petrifaction  of  wood  is  of  the  same 
kind. 

Again  :  cavities  left  empty  by  a  decomposed  crystal,  are 
refilled  by  another  species  by  infiltration,  and  the  new 
mineral  takes  on  the  external  form  of  the  original  mineral, 
as  a  fused  metal  the  form  of  the  mould  into  which  it  is  cast. 

Again  :  crystals  are  sometimes  incrusted  over  by  other 
minerals,  as  cubes  of  fluor  by  quartz  ;  and  when  the  fluor  is 
afterwards  dissolved  away,  as  sometimes  happens,  hollow 
cubes  of  quartz  are  left. 

The  first  kind  of  pseudomorphs,  are  pseudomorphs  by  al- 
teration ;  the  second,  pseudomorphs  by  replacement ;  the 

What  is  a  pseudomorphous  crystal  ?  What  is  the  first,  the  second, 
the  third  and  the  fourth  mode  of  pseudomorphism  1  What  are  they 
called] 

*  From  the  Greek  pseudes,  false,  and  morphe,  form. 


LUSTER    OF    MINERALS.  55 

third,  pseudomorphs  by  infiltration  ;  the  fourth,  pseudomorphs 
by  incrustation* 

Pseudomorphous  crystals  are  distinguished  by  having  a 
different  structure  and  cleavage  from  that  of  the  mineral 
imitated  in  form,  and  a  different  hardness,  and  usually  little 
luster. 

A  large  number  of  minerals  have  been  met  with  as  pseu- 
domorphs. The  causes  of  such  changes  have  operated  very 
widely  and  produced  important  geological  results. 

CHAPTER  III.— PHYSICAL  PROPERTIES  OF 
MINERALS. 

CHARACTERS  DEPENDING  ON  LIGHT. 

The  characters  depending  on  light  are  of  Jive  kinds,  and 
arise  from  the  power  of  minerals  to  reflect,  transmit,  or  emit 
light.  They  are  as  follows  : 

1.  Luster;  2.  Color;  3.  Diaphaneity;  4.  Refraction; 
5.  Phosphorescence. 

LUSTER. 

90.  The  luster  of  minerals  depends  on  the  nature  of  their 
surfaces,  which  causes  more  or  less  light  to  be  reflected. 
There  are  different  degrees  of  intensity  of  luster,  and  also 
different  kinds  of  luster. 

a.  The  kinds  of  luster  are  six,  and  are  named  from  some 
familiar  object  or  class  of  objects. 

1.  Metallic  :  the  usual  luster  of  metals.     Imperfect  me- 
tallic luster  is  expressed  by  the  term  sub-metallic. 

2.  Vitreous  :  the  luster  of  broken  glass.     An  imperfect 
vitreous  luster  is  termed  sub-vitreous.     Both  the  vitreous  and 
sub -vitreous   lusters   are   common.     Quartz   possesses   the 
former  in  an  eminent  degree  ;  calcareous  spar  often  the  lat- 
ter.    This  luster  may  be  exhibited  by  minerals  of  any  color. 

3.  Resinous  :  luster  of  the  yellow  resins.     Ex.  opal,  zinc 
blende. 

4.  Pearly  :  like  pearl.     Ex.  talc,  native  magnesia,  stil- 
bite,  &c.     When  united  with  sub-metallic  luster,  the  term 
metallic -pearly  is  applied. 

How  are  pseudomorphous  crystals  distinguished  1  What  characters 
depend-on  light  ?  Explain  the  varieties  of  luster,  metallic,  vitreous,  &c. 

*  This  subject  is  farther  treated  of  by  the  author  in  the  Araer.  Jour, 
of  Science,  vol.  xlviii,  pp.  66,  81,  397. 


56  PHYSICAL    PROPERTIES    OF   MINERALS. 

5.  Silky :  like  silk  ;  it  is  the  result  of  a  fibrous  structure. 
Ex.  fibrous  carbonate  of  lime,  fibrous   gypsum,  and  many 
fibrous  minerals,  more  especially  those  which  in  other  forms 
have  a  pearly  luster. 

6.  Adamantine  :  the  luster  of  the  diamond.     When  sub- 
metallic,  it  is  termed  metallic-adamantine.     Ex.  some  varie- 
ties of  white  lead  ore. 

b.  The  degrees  of  intensity  are  denominated  as  follows  : 

1.  Splendent :  when  the  surface  reflects  light  with  great 
brilliancy,  and  gives  well  defined  images.     Ex.  Elba  iron 
ore,  tin  ore,  some  specimens  of  quartz  and  pyrites. 

2.  Shining :  when  an  image  is  produced,  but  not  a  well 
defined  image.     Ex.  calcareous  spar,  celestine. 

3.  Glistening :  when  there  is  a  general  reflection  from 
the  surface,  but  no  image.     Ex.  talc,  copper  pyrites. 

4.  Glimmering  :   when  the  reflection  is  very  imperfect, 
and  apparently  from  points  scattered  over  the  surface.     Ex. 
flint,  chalcedony. 

A  mineral  is  said  to  be  dull  when  there  is  a  total  absence 
of  luster.  Ex.  chalk. 

COLOR. 

In  distinguishing  minerals,  both  the  external  color  and  the 
color  of  a  surface  that  has  been  rubbed  or  scratched,  are 
observed.  The  latter  is  called  the  streak,  and  the  powder 
abraded,  the  streak-powder. 

The  colors  are  either  metallic  or  non-metallic. 

The  metallic  are  named  after  some  familiar  metal,  as 
copper-red,  bronze -yellow,  brass-yellow,  gold-yellow,  steel- 
gray,  lead-gray,  iron-gray. 

The  non-metallic  colors  used  in  characterizing  minerals, 
are  various  shades  of  white,  gray,  Hack,  blue,  green,  yellow, 
red  and  brown. 

There  are  thus  snow-white,  reddish- white,  greenish-white, 
milk-white,  yellowish-white ; 

Bluish-gray,  smoke-gray,  greenish-gray,  pearl-gray,  ash- 
gray  ; 

Velvet-black,  greenish-black,  bluish-black  ; 

Azure-blue,  violet-blue,  sky-blue,  Indigo-blue  ; 

Emerald-green,  olive-green,  oil-green,  grass-green,  apple- 
green,  blackish-green,  pistachio-green  (yellowish) ; 

What  is  observed  respecting  color? 


COLOR    OF   MINERALS.  57 

Sulphur-yellow,  straw-yellow,  wax-yellow,  ochre-yellow, 
honey-yellow,  orange-yellow ; 

Scarlet-red,  blood-red,  flesh-red,  brick-red,  hyacinth-red, 
rose-red,  cherry-red ; 

Hair-brown,  reddish-brown,  chesnut-brown,  yellowish- 
brown,  pinchbeck-brown,  wood-brown. 

A  play  of  colors :  this  expression  is  used  when  several 
prismatic  colors  appear  in  rapid  succession  on  turning  the 
mineral.  The  diamond  is  a  striking  example  ;  also  precious 


Change  of  colors  :  when  the  colors  change  slowly  on  turn- 
ing in  different  positions,  as  in  labradorite. 

Opalescence  :  when  there  is  a  milky  or  pearly  reflection 
from  the  interior  of  a  specimen,  as  in  some  opals,  and  in 
cat's  eye. 

Iridescence  :  when  prismatic  colors  are  seen  within  a 
crystal ;  it  is  the  effect  of  fracture,  and  is  common  in 
quartz. 

Tarnish  :  when  the  surface  colors  differ  from  the  interior ; 
it  is  the  result  of  exposure.  The  tarnish  is  described  as 
irised,  when  it  has  the  hues  of  the  rainbow. 

Polychroism  :*  the  property,  belonging  to  some  prismatic 
crystals,  of  presenting  a  different  color  in  different  directions. 
The  term  dichroism^  has  been  generally  used,  and  implies 
different  colors  in  two  directions,  as  in  the  mineral  iolite, 
which  has  been  named  dichroite  because  of  the  different 
colors  presented  by  the  bases  and  sides  of  the  prism.  Mica 
is  another  example  of  the  same.  The  more  general  term  has 
been  introduced,  because  a  different  shade  of  color  has  been 
observed  in  more  than  two  directions. 

These  different  colors  are  observed  only  in  crystals  with 
unequal  axes.  The  colors  are  the  same  in  the  direction  of 
equal  axes,  and  often  unlike  in  the  direction  of  unequal  axes. 
This  is  the  general  principle  at  the  basis  of  polychroism. 


What  is  a  play  of  colors  1  change  of  colors  1  opalescence?  irides- 
cence ?  tarnish  ?  dichroism  and  polychroism  ?  Mention  examples  of 
this  last  property  ;  also  the  law  relating  to  it. 


*  From  the  Greek  polus,  many,  and  chroa,  color. 
tFrom  the  Greek  dis,  twice,  and  chroa. 


58  PHYSICAL    PROPERTIES    OF    MINERALS. 


DIAPHANEITY. 

Diaphaneity  is  the  property  which  many  objects  possess 
of  transmitting  light ;  or  in  other  words,  of  permitting  more 
or  less  light  to  pass  through  them.  This  property  is  often 
called  transparency,  but  transparency  is  properly  one  of  the 
degrees  of  diaphaneity.  The  following  terms  are  used  to 
express  the  different  degrees  of  this  property  : 

Transparent :  a  mineral  is  said  to  be  transparent  when 
the  outlines  of  objects,  viewed  through  it,  are  distinct.  Ex. 
glass,  crystals  of  quartz. 

Subtransparent,  or  semitransparent :  when  objects  are  seen 
but  their  outlines  are  indistinct. 

Translucent :  when  light  is  transmitted,  but  objects  are  not 
seen.  Loaf  sugar  is  a  good  example  ;  also  Carrara  marble. 

Subtranslucent :  when  merely  the  edges  transmit  light 
faintly.  When  no  light  is  transmitted,  the  mineral  is  de- 
scribed as  opaque. 

REFRACTION    AND    POLARIZATION. 

Light  is  always  bent  out  of  its  course  on  passing  from  one 
medium  into  another  of  different  density :  as  from  air  into 
water,  or  from  water  into  air.  This  bending  of  the  rays  of 
light  is  called  refraction.  Thus  if  a  ray  of  light,  as  R  S, 
pass  into  water  at  S,  it  becomes  changed 
in  direction  to  S  U,  instead  of  going 
straight  in  its  course,  R  S  T.  The  line 
a  S  c  is  a  perpendicular  to  the  surface  of 
the  water,  and  the  greater  refraction  of 
the  water  is  seen  by  the  bending  of  the 
•ay  toward  this  perpendicular.  If  a 
circle  be  described  about  S  as  a  center, 
and  the  lines  R  a  and  U  b  be  drawn  perpendicular  to  a  c,  or 
parallel  to  the  surface  of  the  water,  we  see  by  these  lines 
the  exact  relation  between  the  amount  of  refraction  in  these 
two  cases  ;  for  the  refraction  in  water  is  as  much  greater  than 
in  air  as  U  b  is  less  than  R  a.*  This  relation  is  called  the 

What  is  diaphaneity  ?  Explain  the  terms  transparent,  &c.  What 
is  meant  by  refraction  ]  Explain  from  the  figure. 

*  In  mathematical  language,  U  b  is  the  sine  of  the  angle  of  refrac- 
tion, and  a  R  the  sine  of  the  angle  a  S  R,  the  angle  of  incidence  ;  the 
ratio  between  the  two  sines  is  constant,  it  being  alike  for  every  angle  of 
incidence. 


REFRACTION    AND    POLARIZATION    OF   LIGHT.  59 

index  of  refraction.  It  is  about  1 J  for  water,  or  more  accu- 
rately, 1*335.  With  diamond,  the  ray  would  be  bent  in  the 
direct  S  V,  which  indicates  a  much  greater  amount  of  re- 
fraction ;  its  index  is  nearly  2£,  or  correctly,  2.439.  The 
eye  at  R,  looking  into  a  diamond  in  the  direction  R  S,  would 
see  an  object  in  the  direction  of  S  V,  and  not  in  that  of  S  T. 
The  index  of  refraction  has  been  obtained  for  many  sub- 
stances, of  which  the  following  are  a  few : 

Air,  1-000  Calc  spar,  1-654 

Tabasheer,  1-211  Spinel,  1-764 

Ice,  1-308  Sapphire,  1-794 

Cryolite,  1-349  Garnet,  1-815 

Water,  1-335  Zircon,  1-961 

Fluorspar,  1-434  Blende,  2-260 

Rock  salt,  1-557  Diamond,  2-439 

Quartz,  1-548  Chromate  of  lead,    2-974 

DOUBLE  REFRACTION. — Many  crystals  possess  the  pro- 
perty of  refracting  light  in  two  directions,  instead  of  one,  and 
objects  seen  through  them  consequently  appear  double. 
This  is  called  double  refraction.  It  is  most  conveniently 
exhibited  with  a  crystal  of  calc  spar,  and  was  first  noticed 
in  a  pellucid  variety  of  this  mineral  from  Iceland,  called  from 
the  locality  Iceland  spar.  On  drawing  a  line  on  paper  and 
placing  the  crystal  over  it,  two  lines  are  seen  instead  of  one — 
one  by  ordinary  refraction,  the  other  by  an  extraordinary 
refraction.  If  the  crystal,  as  it  lies  over  the  line,  be  turned 
around,  when  it  is  in  one  position  the  two  lines  wTill  come 
together.  Instead  of  a  line,  make  a  dot  on  the  paper,  and 
place  the  crystal  over  the  dot :  the  two  dots  seen  will  not 
come  together  on  revolving  the  crystal,  but  will  seem  to  re- 
volve one  around  the  other.  The  dot  will,  in  fact,  appear 
double  through  the  crystal  in  every  direction  except  that  of 
the  vertical  axis,  and  this  direction  is  called  the  axis  of  double 
refraction.  To  view  it  in  this  direction,  the  ends  must  be 
ground  and  polished.  The  divergence  increases  on  passing 
from  a  view  in  the  direction  of  the  axis  to  one  at  right  angles 
with  it,  where  it  is  greatest.  In  some  substances,  the  re- 
fraction of  the  extraordinary  ray  is  greater  in  the  latter 
direction  than  that  of  the  ordinary  ray,  and  in  others  it  is  less. 

What  is  double  refraction  1  What  takes  place  on  revolving  a  trans- 
parent rhomb  of  calc  spar  over  a  line  or  dot  ?  In  what  direction  is  there 
no  double  refraction,  and  in  which  is  it  greatest  ? 


60 


PHYSICAL    PROPERTIES    OF    MINERALS. 


In  calc  spar  it  is  less,  it  diminishing  from  1'654  to  1-483. 
In  quartz  it  is  greater,  it  increasing  from  1*5484  to  T5582. 
The  former  is  said  to  have  a  negative  axis,  the  latter  a 
positive. 

This  property  of  double  refraction  belongs  to  such  of  the 
fundamental  forms  as  have  unequal  axes ;  that  is,  to  all  except 
those  of  the  monometric  system.  Those  forms  in  which  the 
lateral  axes  are  equal,  (the  dimetric  and  hexagonal  systems,) 
have  one  axis  of  double  refraction ;  and  those  in  which  they 
are  unequal,  (the  trimetric,  monoclinate  and  triclinate  sys- 
tems,) have  two  axes  of  double  refraction.* 

Both  rays  in  the  latter  are  rays  of  extraordinary  refraction. 
In  niter,  the  two  axes  are  inclined  about  5°  to  each  other  ; 
in  arragonite,  18  18  ;  in  topaz,  65°.  The  positions  of  the 
axes  thus  vary  widely  in  different  minerals. 

POLARIZATION. — The  extraordinary  ray  exhibits  a  pecu- 
liar property  of  light,  termed  polarization.  Viewed  by  means 
of  another  doubly-refracting  crystal,  or  crystalline  plate, 
(called  from  this  use  of  it  an  analyzing  plate,)  the  ray  of  light 
becomes  alternately  visible  and  invisible  as  the  latter  plate 
is  revolved.  If  the  polarized  light  be  made  to  pass  through 
a  crystal  possessed  of  double  refraction,  and  then  be  viewed 
in  the  manner  stated,  rings  of  prismatic  colors  are  developed, 
93  94  95 


and  on  revolving  the  analyzing  plate,  the  colored  rings  and 

What  is  meant  by  positive  and  negative  double  refraction  ?  What 
crystalline  forms  exhibit  double  refraction  ?  which  have  one  and  which 
two  axes  of  double  refraction  1  What  are  the  effects  due  to  polarization  ? 

*  The  figures  in  the  note  to  page  42,  represent  the  form  of  the  mole- 
cules corresponding  to  these  three  conditions  :  1,  a  sphere;  2,  an  ellip- 
soid with  equal  transverse  axes  ;  3,  an  ellipsoid  with  unequal  lateral 


PHOSPHORESCENCE.  61 

intervening  dark  rings  successively  change  places.  If  crys- 
talline plates,  having  one  axis  of  double  refraction,  be  viewed 
in  the  direction  of  the  axis,  the  rings  are  circles,  and  they 
are  crossed  by  a  dark  or  light  cross.  Figure  93  shows  the 
position  of  the  colored  rings  and  cross  in  calc  spar,  and 
figure  94,  the  same  at  intervals  of  90 3  in  the  revolution  of 
the  plate.  With  a  crystal  having  two  axes  of  double  refrac- 
tion, there  are  two  series  of  elliptical  rings,  as  in  figures  95, 
96  ;  these  figures  show  the  character  of  the  rings  in  niter, 
the  latter  alternating  with  the  former  in  the  revolution  of  the 
plate. 

The  same  results  are  produced  when  the  light  is  polarized 
by  other  means.  For  example,  if  a  ray  of  light  be  reflected 
from  a  plate  of  glass  at  a  certain  angle,  (56 D  45',)  it  is  polar- 
ized ;  and  on  causing  this  ray  to  pass  through  crystals,  as 
above,  similar  rings  are  shown  with  the  same  succession  of 
changes  on  revolving  the  analyzing  plate. 

There  are  some  monometric 
crystals  which  have  the  property 
of  polarization.  The  accompany- 
ing  figure  of  a  crystal  of  analcime, 
by  Sir  David  Brewster,  exhibits  a 
singular  symmetrical  arrangement 
of  lines  of  prismatic  colors  and 
dark  alternating  lines  with  cross 
bands,  producing  a  very  brilliant 
effect.  An  irregular  polarization 
has  also  been  detected  in  some 
diamonds. 

PHOSPHORESCENCE . 

Several  minerals  give  out  light  either  by  friction  or  when 
gently  heated.  This  property  of  emitting  light  is  called 
phosphorescence. 

Two  pieces  of  white  sugar  struck  against  one  another  give 
a  feeble  light,  which  may  be  seen  in  a  dark  place.  The 
same  effect  is  obtained  on  striking  together  fragments  of 
quartz,  and  even  the  passing  of  a  feather  rapidly  over  some 
specimens  of  zinc  blende,  is  sufficient  to  elicit  light. 

Fluor  spar  is  the  most  convenient  mineral  for  showing 
phosphorescence  by  heat.  On  powdering  it,  and  throwing 

What  is  said  of  the  appearance  of  certain  crystals  in  polarized  light  1 
What  is  phosphorescence  I  Mention  examples  explaining  the  different 
modes  of  exhibiting  it. 

6 


62  PHYSICAL    PROPERTIES    OF    MINERALS. 

it  on  a  shovel  heated  nearly  to  redness,  the  whole  takes  OH 
a  bright  glow.     In  some  varieties,  the  light  is  emerald  green ; 
in  others,  purple,  rose,  or  orange.     A  massive  fluor,  from 
Huntington,    Connecticut,    shows    beautifully   the    emerald . 
green  phosphorescence. 

Some  kinds  of  white  marble,  treated  in  the  same  way, 
give  out  a  bright  yellow  light. 

After  being  heated  for  a  while,  the  mineral  loses  its 
phosphorescence  ;  but  a  few  electric  shocks  will,  in  many 
cases,  to  some  degree,  restore  it  again. 

ELECTRICITY    AND    MAGNETISM. 

ELECTRICITY. — Many  minerals  become  electrified  on 
being  rubbed,  so  that  they  will  attract  cotton  and  other  light 
substances ;  and  when  electrified,  some  exhibit  positive,  and 
others  negative  electricity,  when  brought  near  a  delicately 
suspended  magnetic  needle.  The  diamond,  whether  polished 
or  not,  always  exhibits  positive  electricity,  while  other  gems 
become  negatively  electric  in  the  rough  state,  and  positive 
only  in  the  polished  state.  Friction  with  a  feather  is  suffi- 
cient to  excite  electricity  in  some  varieties  of  blende.  Some, 
minerals,  thus  electrified,  retain  the  power  of  electric  attrac- 
tion for  many  hours,  as  topaz,  while  others  lose  it  in  a  few 
minutes. 

Many  minerals  become  electric  when  heated,  and  such 
species  are  said  to  be  pyro-electric,  from  the  Greek  pur,  fire, 
and  electric. 

If  a  prism  of  tourmaline,  after  being  heated,  be  placed  on 
a  delicate  frame,  which  turns  on  a  pivot  like  a  magnetic 
needle,  on  bringing  a  magnet  near  it,  one  extremity  will  be 
attracted,  the  other  repelled,  thus  indicating  the  polarity  al- 
luded to.  The  same  is  better  shown  if  the  ends  of  the  crystal 
be  brought  near  the  poles  of  a  delicately  suspended  magnetic 
needle.  The  prisms  of  tourmaline  have  different  secondary 
planes  at  the  two  extremities,  or,  as  it  is  expressed,  are  hemi- 
hedrally  modified  (page  37.) 

Several  other  minerals  have  this  peculiar  electric  property, 
especially  boracite  and  topaz,  which,  like  tourmaline,  are 
hemihedral  in  their  modifications.  Boracite  crystallizes  in 

Will  electricity  restore  the  phosphorescent  property  when  it  is  lost  by 
heating  a  mineral  ?  What  two  modes  are  there  of  exciting  electricity 
in  minerals  1  What  is  said  of  the  diamond  as  compared  with  other 
gems  ?  What  is  a  pyro-electric  1  What  is  said  of  tourmaline  1  what 
of  topaz  and  boracite  1 


SPECIFIC    GRAVITY.  63 

cubes,  with  only  the  alternate  solid  angles  similarly  replaced 
(figs.  40,  41,  page  37.)  Each  solid  angle,  on  heating  the 
crystals,  becomes  an  electric  pole  ;  the  angles  diagonally 
opposite,  are  differently  modified  and  have  opposite  polarity. 

MAGNETISM. — Lodestone  includes  certain  specimens  of  an 
ore  of  iron,  called  magnetic  oxyd  of  iron,  having  the  power 
of  attraction  like  a  magnet ;  it  is  common  in  many  ore  beds 
where  this  ore  of  iron  occurs.  When  mounted  like  a  horse- 
shoe magnet,  a  good  lodestone  wrill  lift  a  weight  of  many 
pounds.  This  is  the  only  mineral  that  has  decided  magnetic 
attraction.  But  several  ores  containing  iron  are  attracted  by 
the  magnet,  or,  when  brought  near  a  magnetic  needle,  will 
cause  it  to  vibrate  ;  and  moreover,  the  metals  nickel,  cobalt, 
manganese,  palladium,  platinum  and  osmium,  have  been 
found  to  be  slightly  magnetic. 

Many  minerals  become  attractable  by  the  magnet  after 
being  heated,  that  are  not  so  before  heating.  This  arises 
from  a  partial  reduction,  developing  the  protoxyd  of  iron. 

SPECIFIC    GRAVITY. 

The  specific  gravity  of  a  mineral  is  its  \veight  compared 
with  that  of  some  substance,  taken  as  a  standard.  For  solids 
and  liquids,  distilled  water  at  60'  F.  is  the  standard  ordinarily 
used ;  and  if  a  mineral  weighs  twice  as  much  as  water,  its 
specific  gravity  is  2  ;  if  three  times,  it  is  3.  It  is  then 
necessaiy  to  compare  the  weight  of  the  mineral  with  the 
weight  of  an  equal  bulk  of  water.  The  process  is  as  follows  : 

First  weigh  a  fragment  of  the  mineral  in  the  ordinary  way, 
with  a  delicate  pair  of  scales  :  next  sus-  98 

pend  the  mineral  by  a  hair  or  fiber  of  , 

silk  to  one  of  the  scales,  immerse  it  thus 
suspended  in  a  tumbler  of  water,  (keep- 
ing the  scales  clear  of  the  water,)  and 
weigh  it  again :  subtract  the  second  weight 
from  theirs/,  to  ascertain  the  loss  by  im- 
mersion, and  divide  the  first  by  the  dif-    afca 
ference  obtained  :  the  result  is  the  spe-     DM 
cific  gravity.     The  loss  by  immersion  is 

What  ore  is  at  times  possessed  of  magnetic  attraction  ?  What  is 
said  of  other  minerals  as  regards  magnetism  ?  What  is  specific  gravity  1 
Explain.  Mention  the  mode  of  ascertaining  specific  gravity. 


64  PHYSICAL    PROPERTIES    OF   MINERALS. 

equal   to  the  weight  of  the    same  bulk  of  water  as  the 
mineral.* 

A  better  and  more  simple  process  than  the  above,  and  one 
available  for  porous  as  well  as  compact  minerals,  is  per- 
formed with  a  light  glass  bottle,  capable  of  holding  exactly  a 
thousand  grains  (or  any  known  weight)  of  distilled  water. 
The  specimen  should  be  reduced  to  a  coarse  powder.  Pour 
out  a  few  drops  of  water  from  the  bottle,  and  weigh  it ;  then 
add  the  powdered  mineral  till  the  water  is  again  to  the  brim, 
and  reweigh  it :  the  difference  in  the  two  weights,  divided 
by  the  loss  of  water  poured  out,  is  the  specific  gravity  sought. 
The  weight  of  the  glass  bottle  itself  is  here  supposed  to  be 
balanced  by  an  equivalent  weight  in  the  other  scale. 

HARDNESS. 

The  comparative  hardness  of  minerals  is  easily  ascer- 
tained, and  should  be  the  first  character  attended  to  by  the 
student  in  examining  a  specimen.  It  is  only  necessary  to 
draw  the  file  across  the  specimen,  or  to  make  trials  of  scratch- 
ing one  with  another.  As  standards  of  comparison,  the 
following  minerals  have  been  selected,  increasing  gradually 
in  hardness  from  talc,  which  is  very  soft  and  easily  cut  with 
a  knife,  to  the  diamond,  which  nothing  will  cut.  This  table 
is  called  the  scale  of  hardness. 

1,  talc,  common  foliated  variety  ;  2,  rock  salt;  3,  calc  spar, 
transparent  variety ;  4,  fluor  spar,  crystallized  variety;  5, 
apatite,  transparent  crystal ;  ,6,  feldspar,  cleavable  variety  ; 
7,  quartz,  transparent  variety  ;  8,  topaz,  transparent  crystal ; 
9,  sapphire,  cleavable  variety;  10,  diamond. 

If  on  drawing  a  file  across  a  mineral,  it  is  impressed  as 
easily  asfluor  spar,  the  hardness  is  said  to  be  4 ;  if  as  easily 
a.sfeldspar,ihe  hardness  is  said  to  be  6  ;  if  more  easily  than 

What  other  mode  is  fitted  for  porous  as  well  as  compact  minerals  1 
How  is  the  hardness  of  minerals  ascertained  ?  What  is  the  scale  of 
hardness  1  Explain  its  use.  What  directions  are  given  for  trials  of 
hardness  ? 

*  For  perfectly  accurate  results,  the  most  delicate  scales  and  weights 
should  be  used,  and  great  care  be  observed  in  the  trial.  The  purity  and 
temperature  of  the  water  should  also  be  attended  to,  and  the  height  of 
the  barometer.  For  the  latter,  an  allowance  is  made  for  any  variation 
from  a  height  of  30  inches.  The  temperature  of  water  at  its  maximum 
density,  or  at  39°  1  F.,  is  recommended  as  preferable  to  60°  F. 


FRACTURE.  65 

I 

feldspar,  but  with  more  difficulty  than  apatite,  its  hardness  is 
described  as  5£  or  5'5. 

The  file  should  be  run  across  the  mineral  three  or  four 
times,  and  care  should  be  taken  to  make  the  trial  on  angles 
equally  blunt,  and  on  parts  of  the  specimen  not  altered  b} 
exposure.  Trials  should  also  be  made  by  scratching  the 
specimen  under  examination  with  the  minerals  in  the  above 
scale,  as  sometimes,  owing  to  a  loose  aggregation  of  particles, 
the  file  wears  down  the  specimen  rapidly,  although  the  par- 
ticles are  very  hard. 

STATE    OP   AGGREGATION. 

Solid  minerals  may  be  either  brittle,  sectile,  malleable, 
flexible  or  elastic.  Fluids  are  either  gaseous  or  liquid. 

1.  Brittle  :  when  parts  of  the  mineral  separate  in  powder 
on  attempting  to  cut  it. 

2.  Seclile  :  when  thin  pieces  may  be  cut  off  with  a  knife 
but  the  mineral  pulverises  under  a  hammer. 

3.  Malleable  :  when  slices  may  be  cut  off,  and  these  slices 
will  flatten  out  under  the  hammer.     Example,  native  gold 
and  silver. 

4.  Flexible  :  when  the  mineral  will  bend,  and  remain  bent 
after  the  bending  force  is  removed.     Example,  talc. 

5.  Elastic  :  when  after  being  bent,  it  will  spring  back  to 
its  original  position.     Example,  mica. 

A  liquid  is  said  to  be  viscous,  when  on  pouring  it  the  drops 
lengthen  and  appear  ropy.  Example,  petroleum. 

FRACTURE. 

The  following  are  the  several  kinds  of  fracture  in  minerals  : 

1.  Conchoidal :  when  the  mineral  breaks  with  a  curved, 
or  concave  and  convex  surface  of  fracture.     The  word  con- 
choidal  is  from  the  Latin  concha,  a  shell.     Flint  is  a  good 
example. 

2.  Even  :  when  the  surface  of  fracture  is  nearly  or  quite 
flat. 

3.  Uneven  :  when  the  surface  of  fracture  is  rough  with 
numerous  small  elevations  and  depressions. 

4.  Hackly :  when  the  elevations  are  sharp  or  jagged,  as 
in  broken  iron. 

Explain  the  use  of  the  term  brittle  ;  sectile  ;  malleable,  &c.     Explain 
the  use  of  the  term  conchoidal ;  even  ;  uneven. 
6* 


66        CHEMICAL  PROPERTIES  OF  MINERALS. 


TASTE. 

Taste  belongs  only  to  the  soluble  minerals ;  the  kinds  are— 

1.  Astringent:  the  taste  of  vitriol. 

2.  Sweetish-astringent :  the  taste  of  alum. 

3.  Saline  :  taste  of  common  salt. 

4.  Alkaline  :  taste  of  soda. 

5.  Cooling  :  taste  of  saltpeter. 

6.  Bitter  :  taste  of  epsom  salts. 

7.  Sour:  taste  of  sulphuric  acid. 

ODOR. 

Excepting  a  few  gases  and  soluble  minerals,  minerals  in 
the  dry,  unchanged  state,  do  not  give  off  odor.  By  friction, 
moistening  with  the  breath,  the  action  of  acids  and  the  blow- 
pipe, odors  are  sometimes  obtained,  which  are  thus  designated : 

1.  Alliaceous  :  the  odor  of  garlic.     It  is  the  odor  of  burn- 
ing arsenic,  and  is  obtained  by  friction  and  more  distinctly 
by  means  of  the  blowpipe  from  several  arsenical  ores. 

2.  Horse-radish  odor  :  the  odor  of  decaying  horse-radish. 
It  is  the  odor  of  burning  selenium,  and  is  strongly  perceived 
when  ores  of  this  metal  are  heated  before  the  blowpipe. 

3.  Sulphureous :  odor  of  burning  sulphur.     Friction  will 
elicit  this  odor  from  pyrites,  and  heat  from  many  sulphurets. 

4.  Fetid  :  the  odor  of  rotten  eggs  or  sulphuretted  hydrogen. 
It  is  elicited  by  friction  from  some  varieties  of  quartz  and 
limestone. 

5.  Argillaceous:  the  odor  of  moistened  clay.     It  is  given 
off  by  serpentine  and  some  allied  minerals  when  breathed 
upon.     Others,  as  pyrargillite,  afford  it  when  heated. 

CHAPTER  IV.— CHEMICAL  PROPERTIES  OF 
MINERALS. 

ACTION    OF   ACIDS. 

Acids  are  used  in  distinguishing  certain  minerals  that  are 
decomposed  by  them.  The  acids  employed  are  either  the 
sulphuric,  muriatic,  or  nitric.  Carbonate  of  lime,  (calca- 

What  taste  is  astringent  1  sweetish  astringent  1  saline  ?  What  will 
develop  odor  in  some  minerals  ]  What  is  understood  by  an  alliaceous 
odor  ?  What  mineral  when  heated  produces  this  odor  1  What  is  the 
odor  of  fumes  of  selenium  1  How  is  a  sulphureous  odor  obtained  from 
certain  minerals  1  What  gas  has  a  fetid  odor  1  What  is  an  argilla- 
ceous odor  ? 


CSE    OF   THR   BLOWPIPE. 


67 


reous  spar,)  when  dropped  into  either  of  these  acids  gives  off 
bubbles  of  gas,  which  effect  is  called  effervescence.  The 
same  result  takes  place  with  some  other  minerals.  The 
acid  used  in  these  tests,  should  be  half  water ;  and  to  avoid 
error,  it  is  best  to  put  a  little  of  it  in  a  test  tube,  and  drop  in 
small  fragments  of  the  coarsely  powdered  mineral.  Some- 
times heat  will  cause  an  effervescence,  which  does  not  take 
place  with  cold  acid.  Often  effervescence  arises  from  some 
impurity  present,  which  is  discontinued  before  the  solution 
of  the  mineral  in  the  acid  is  complete. 

Other  minerals,  that  do  not  effervesce  in  the  acids,  be- 
come changed  to  a  jelly-like  mass.  For  trials  of  this  kind, 
the  strong  acids  should  generally  be  used.  The  powdered 
mineral  is  allowed  to  remain  for  a  while  in  the  acid,  and 
gradually  a  jelly-like  mass  is  formed.  Often  heat  is  required, 
and  in  that  case,  the  jelly  appears,  as  the  solution  cools. 
The  minerals  belonging  to  the  zeolite  family  more  especially 
undergo  this  change  from  the  action  of  acids,  and  it  arises 
from  the  separation  of  their  silica  in  a  gelatinous  state. 


100 


BLOWPIPE. 

To  ascertain  the  effect  of  heat  on  minerals,  &  small  instru- 
ment is  used  called  a  blow- 
pipe. In  its  simplest  form, 
(fig.  100,)  it  is  merely  a  bent 
tube  of  small  size,  8  to  10 
inches  long,  terminating  at 
one  end  in  a  minute  orifice, 
not  larger  than  a  pin  hole. 
it  is  used  to  concentrate  the 
flame  of  a  candle  or  lamp  on 
a  mineral,  and  this  is  done 
by  blowing  through  it  while 
the  smaller  end  is  just  within 
the  flame. 

Figures  101  and  102  are 
other  forms  of  the  blowpipe, 
containing  air  chambers  (o) 
to  receive  the  moisture  which 
is  condensed  in  the  tube 

What  is  effervescence,  and  how  produced  ?  How  should  the  acid  be 
used  ?  How  are,  some  minerals  made  to  gelatinize  ?  On  what  does 
iiis  property  depend  ?  What  is  the  object  of  a  blowpipe  ? 


68         CHEMICAL  PROPERTIES  OF  MINERALS. 


during  the  blowing ;  the  moisture,  unless  thus  removed,  is 
often  blown  through  the  small  aperture  and  interferes  with 
the  experiment.  The  air  chamber  in  figure  102  is  a  cylin- 
der, into  which  the  tube  a  b  c  is  screwed  at  c,  and  the  small- 
er piece  d  e  f,  at  d.  For  the  convenience  of  packing  it 
away,  there  is  a  screw  at  b.  The  part  b  c,  after  unscrewing 
it,  may  be  run  into  the  part  a  I,  through  the  large  end,  (a,) 
and  screwed  up  again,  and  thus  it  is  half  the  length  it  has 
when  arranged  for  use.  The  mouth  piece  e  f  screws  off, 
and  is  made  of  platinum  in  order  that  it  may  be  cleaned  when 
necessary  by  immersion  in  an  acid.  The  best  material  for 
the  blowpipe  is  silver,  or  if  a  cheaper  material  is  desired, 
tinned  iron  with  the  piece  efof  brass.  Brass  gives  a  dis- 
agreeable smell  to  the  moist  fingers. 

In  using  the  blowpipe,  it  is  necessary  to  breathe  and  blow 
at  the  same  time,  that  the  operator  may  not  interrupt  the 
flame  in  order  to  take  breath.  Though  seemingly  absurd, 
the  necessary  tact  may  easily  be  acquired.  Let  the  student 
first  breathe  a  few  times  through  his  nostrils,  while  his  cheeks 
are  inflated  and  his  mouth  closed.  After  this  practice,  let 
him  put  the  blowpipe  to  his  mouth,  and  he  will  find  no  diffi- 
culty in  breathing  as  before ;  while  the  muscles  of  the  in- 
flated cheeks  are  throwing  the  air  they  contain  through  the 
blowpipe.  When  the  air  is  nearly  exhausted,  the  mouth  may 
again  be  filled  through  the  nose  without  interrupting  the 
process  of  blowing. 

A  lamp  with  a  large  wick,  so  as  to  give  a  broad  flame, 
and  fed  with  olive  oil,  is  best ;  but  a  candle  is  more  conve- 
niently carried  about  when  travelling.  The  wick  should  be 
bent  in  the  direction  the  flame  is  to  be  blown. 

The  flame  has  the  form  of  a  cone,  yellow  without  and  blue 
within.  The  heat  is  most  intense  just  beyond  the  extremity 
of  the  blue  flame.  In  some  trials,  it  is  necessary  that  the 
air  should  not  be  excluded  from  the  mineral  during  the  ex- 
periment, and  when  this  is  the  case,  the  outer  flame  is  used. 
The  outer  is  called  the  oxydating*  flame,  and  the  inner  the 
reducing  flame. 

Explain  the  structure  and  mode  of  use.  Whai,  is  said  of  the  flame 
of  a  candle  before  the  blowpipe  ?  Which  is  the  oxydating,  and  which 
the  reducing  flame  1 

*  It  is  so  called  because  when  thus  heated,  oxygen,  one  of  the  con- 
stituents of  the  atmosphere,  combines  in  many  cases  with  some  parts 
of  the  assay  (or  substance  under  experiment.) 


USE    OF   THE    BLOWPIPE.  69 

The  mineral  is  supported  in  the  flame,  either  on  charcoal, 
or  by  moans  of  steel  forceps,  (fig.  103,)  with  platinum  ex- 
tremities {a  b)  ;  the  forceps  are  opened  by  pressing        103 
on  the  pins  p  p.     The   charcoal  should  be  firm 
and  well  burnt.     Charcoal  is  especially  necessary 
when  the  reduction  of  the  assay  needs  the  presence 
of  carbon ;  and  platinum  when  simple  heat  is  re- 
quired.    Platinum  foil  for  enveloping  the  mineral, 
and   small  platinum  cups  are  also  used.     When 
nothing  better  is  at  hand,  the  mineral  mica  or  kyan- 
ite  may  be  employed.     The  fragment  of  mineral 
under  trial  should  be  less  than  half  a  pea  in  size, 
and  often  a  thin  splinter  is  required. 

To  test  the  presence  of  water  or  a  volatile  ingre- 
dient, the  mineral  is  heated  In  a  glass  tube  or  test 
vial.  The  tube  may  be  three  or  four  inches  long 
and  as  large  as  a  quill.  The  flame  is  directed 
against  the  exterior  of  the  tube  beneath  the  assay, 
and  the  volatilized  substance  usually  condenses  in 
the  upper  part  of  the  tube.  By  inserting  into  the 
upper  end  of  the  tube  a  strip  of  litmus  or  other 
lest  paper,  it  is  ascertained  whether  the  fumes  are 
acid  or  not. 

Some  species  require  for  fusion  the  aid  of  what  are 
ca\\edf,uxes.  Those  more  commonly  used  are  borax, 
salt  of  phosphorus,  and  carbonate  of  soda.  They 
are  fused  to  a  clear  globule,  to  which  the  mineral  is 
added;  or  powdered  and  made  up  into  a  ball  with 
the  moistened  mineral  in  powder.  In  this  way 
some  minerals  are  fused  that  cannot  be  attacked 
otherwise,  and  nearly  all  species,  as  they  melt,  un- 
dergo certain  changes  in  color,  arising  from  changes 
in  composition,  which  are  mentioned  in  describing 
minerals. 

The  above  mentioned  fluxes  also  are  often  required  in 
order  to  obtain  the  metals  from  the  metallic  ores.  On  heat- 
ing a  fragment  of  copper  pyrites  with  borax,  a  globule  of 
copper  is  obtained ;  and  tin  ore  heated  with  soda  yields  a 
globule  of  tin. 

What  instruments  of  appliances  are  used  for  holding  minerals  before 
the  blowpipe  ?  How  is  the  presence  of  water  ascertained  ?  How  may 
its  acidity  be  tested  ?  How  are  the  common  fluxes  employed,  and 
what  is  their  «.:e  2 


70 


CHEMICAL   PROPERTIES    OF   MINERALS. 


The  following  table  contains  the  reactions  of  some  of  the 
metallic  oxyds  with  the  ordinary  fluxes  :* 


Borax. 

Salt  of  Phosphorus. 

Soda. 

Titanic  acid 

O,  colorless  or 

O,  colorless,  trp 

Deep  yw,  hot  ; 

milky 

worgyh,cold 

Oxyd  of  iron 

0,red,hot;ywh 
or   colorless, 

O,  red,  hot;  paler  or 
colorless,  cold 

cold 

R,  green  or  bh 

Oxyd  of  cerium 

gn 
O,   r  ;    yw  on 

O,  fine  r,  hot  ;  col- 

cooling ;    w 

orless,  cold 

enamel    on 

flaming 

R,  colorless   or 

w  enamel 

Oxyd  of  manga- 

0, amethystine 

O.  amethystine 

PL  trp  gn,hot; 

nese 

bh-gn,  cold 

Oxyd  of  cobalt 

O,  trp  blue 

O,  blue 

PI.  pale  r,  hot  ; 

gray,  cold 

Oxyd  of  chrome 

O,bn,hot;  pale 

O,  green 

O.  PI.  dull  or- 

gn, cold 

ange  ;  op  &  y  w 

R,  emerald-gn, 

R,  green 

on  cooling 

cold 

Oxyd  of  copper 

O,  green 
R,    colorless, 

O,  green 
R,  colorless,  hot  ;  r 

PZ.gn,hot;  col, 
op,  cold 

hot  ;  but  sud- 

on solidifying 

denly  opaque 

and    rdh   on 

cooling 

The  following  are  other  reactions  : 

Nitrate  of  cobalt  in  solution  added  to  the  assay  after  heat- 
ing  to  redness,  and  then  again  heated,  produces  before  fusion 
a  blue  color  for  alumina  and  a  pale-red  for  magnesia. 

Boracic  acid  fused  with  a  phosphate  produces  a  globule, 
into  which  if  the  extremity  of  a  small  iron  wire  be  inserted, 
and  the  whole  heated  in  the  reduction  flame,  the  globule  at- 
tached to  the  wire  will  be  brittle,  as  proved  by  striking  it 
with  a  hammer  on  an  anvil.  Before  this  trial  it  should  be 
ascertained  that  no  sulphuric  or  arsenic  acid  is  present,  which 
also  may  form  a  brittle  globule  with  the  iron  ;  nor  any 
metallic  oxyd  reducible  by  the  iron. 


For  what  is  nitrate  of  cobalt  used  1 
acid  used  1 


How  and  for  what  is  boracio 


*  O  stands  for  oxydating  flame  ;  R  for  reducing  flame  ;  Ch  for  char- 
coal ;  trp  for  transparent ;  bh  bluish  ;  yw  yellow  ;  gn  green  ;  r  red  ; 
gyh  grayish  ;  w  white  ;  PI  in  platinum  forceps  ;  op  opaque. 


CLASSIFICATION    OF    MINERALS.  71 

Tin-foil  is  used  to  fuse  with  certain  peroxyds  of  metals  to 
reduce  them  to  protoxyds.  The  assay,  previously  heated  in 
the  reducing  flame,  should  be  touched  with  the  end  of  the 
tin  foil ;  a  very  minute  quantity  of  a  metallic  oxyd  is  thus 
detected. 

Saltpeter  added  along  with  a  flux  to  a  compound  contain- 
ing manganese,  gives  the  amethystine  color,  when  the  quan- 
tity is  too  small  to  be  detected  without  it. 

Potash  salts,  if  there  is  no  soda  present,  give  a  slightly 
violet  tinge  to  the  flame. 

Soda  salts  give  the  flame  a  deep  yellow  color. 

LUhia  salts  give  the  flame  a  reddish  tinge  ;  the  silicates 
require  the  addition  of  some  fluor  spar  and  bisulphate  of  pot- 
ash. By  adding  soda  and  heating  on  platinum,  the  lithia 
stains  the  platinum  brown. 

Sulphurets,  Sulphat.es.  A  glass  made  of  soda  and  silica 
becomes  red  or  orange  yellow  when  sulphur  is  present. 
Heated  on  charcoal  with  soda,  and  then  adding  a  drop  of 
water,  they  yield  sulphuretted  hydrogen,  which  blackens  a 
test  paper  containing  acetate  of  lead.  Sulphurets  heated  in 
a  glass  tube  closed  below,  with  litmus  paper  above,  redden 
the  litmus  paper,  and  yield  usually  a  sulphureous  odor. 

Seleniets  give  off  a  horse-radish  odor. 

Arseniurets  give  off  an  odor  like  garlic,  which  is  brought 
out  by  heating  with  soda  in  the  reduction  flame,  if  not  other- 
wise perceptible  ;  heated  in  a  tube,  orpiment  is  condensed. 

Fluorids.  Heated  with  salt  of  phosphorus,  previously 
melted  in  a  glass  tube,  the  glass  is  corroded ;  and  Brazil 
paper  placed  in  the  tube  becomes  yellow.  The  salt  of 

losphorus  for  this  trial  should  be  free  from  all  chlorids. 
ritrates  detonate  on  burning  coals. 

CHAP.  V.— CLASSIFICATION  OF  MINERALS. 

Under  the  term  mineral,  as  explained,  are  included  all 
inorganic  substances  occurring  in  nature.  These  substan- 
ces have  been  found  to  consist  of  various  elements,  some  few 

How  and  for  what  is  tin-foil  used  ?  saltpeter  1— What  is  said  of  the 
constitution  of  minerals  1 

*  For  full  information  on  the  use  of  the  blowpipe  and  its  reactions, 
there  is  no  better  work  than  Berzelius  on  "  the  Use  of  the  Blowpipe," 
translated  by  J.  0.  Whitney.  238  pp.  8vo.  Boston,  1845. 


72  CLASSIFICATION    OF   MINERALS. 

species  being  each  a  simple  element  alone,  and  others  con- 
sisting of  two  or  more  elements  in  a  state  of  combination, 
The  various  native  metals,  as  native  gold,  silver,  copper, 
mercury,  are  some  of  the  elements.  Iron  ores  are  com- 
pounds of  the  element  iron  with  some  other  element  or 
elements,  as  oxygen,  sulphur,  or  oxygen  and  carbon,  &e, 
Marble  is  a  compound  of  three  elements,  calcium,  oxygen 
and  carbon.  Water  consists  of  two  elements,  hydrogen  and 
oxygen.  Diamond  is  the  simple  element  carbon,  which  is 
identical  with  pure  charcoal.  All  the  so-called  elements  of 
matter  are  found  in  the  mineral  kingdom,  either  in  a  pure  or 
combined  state ;  and  it  is  the  object  of  chemical  analysis 
to  ascertain  the  proportions  of  each  in  the  constitution  of 
the  several  minerals.  Upon  these  results  depends  to  a  great 
degree  our  knowledge  of  those  relations  of  the  species  upon 
which  the  classification  of  minerals  is  based. 

The  number  of  elemental  substances  in  nature,  according 
to  the  most  recent  results  of  chemistry,  is  fifty-nine.  Of 
these,  forty-three  are  metals,  and  five  are  gases  ;  the  re- 
mainder, as,  for  instance,  sulphur  and  carbon,  are  solids 
without  a  metallic  luster,  excepting  one  (bromine)  which  is 
a  liquid  at  the  ordinary  temperature.  Of  these  fifty-cine 
elements,  very  much  the  larger  part  are  of  rare  occurrence 
in  nature.  The  rocks  of  the  globe,  with  their  most  common 
minerals,  are  made  up  of  about  thirteen  of  the  elements. 
These  are  the  gases  oxygen,  hydrogen,  nitrogen,  chlorine ; 
the  non-metallic  elements  carbon,  sulphur,  silicon  j  the  metals 
calcium,  (basis  of  lime,)  sodium,  (basis  of  soda,)  potassium, 
(basis  of  potash,)  magnesium,  (basis  of  magnesia,)  aluminium, 
(basis  of  alumina,  the  principle  constituent  of  clay,)  with 
iron.  The  element  silicon  combined  with  oxygen,  forms 
silica.  In  this  state,  it  is  the  mineral  quartz,  the  most 
common  in  the  constitution  of  the  rocks  of  the  globe :  it 
is  a  constituent  of  granite,  mica  slate  and  the  allied  rocks, 
of  the  hard  granular  quartz  rock  ;  and  it  is  the  essential  part 
of  all  sandstones  and  millstone  grits,  as  well  as  the  principal 
ingredient  of  the  sands  of  the  sea  shore  and  of  most  soils. 
Combined  with  lime,  potash  or  soda,  magnesia  or  alumina, 
and  often  with  iron,  it  forms  nearly  all  the  other  mineral  in- 


What  is  the  number  of  elements,  and  how  many  nre  metals  ?  How 
many  constituents  are  essential  to  the  rocks  of  the  globe,  and  what  are 
they  1  What  is  said.,  of  quartz  ? 


CLASSIFICATION   OF   MINERALS.  73 

gradients  of  granite,  mica  slates,  volcanic  rocks,  shales, 
sandstones  and  various  soils.  No  element  is  therefore  more 
important  than  this  in  the  constitution  of  the  earth's  strata : 
and  it  is  specially  fitted  for  this  preeminence  by  its  superior 
hardness,  a  character  it  communicates  to  the  rocks  in  which 
it  prevails.  Next  to  silica,  rank  lime  and  carbon  ;  for  carbon 
with  oxygen  constitutes  carbonic  acid,  and  this  combined 
with  lime,  produces  carbonate  of  lime,  the  ingredient  which, 
when  occurring  in  extended  beds,  we  call  limestone  and 
marble.  Again,  lime  combined  with  sulphur  and  oxygen, 
(sulphuric  acid,)  makes  sulphate  of  lime,  or  common  gypsum. 
Iron  is  very  generally  diffused  ;  it  is  one  of  the  constituents 
of  many  siliceous  minerals,  and  forms  vast  beds  of  ore. 
Oxygen,  as  has  been  implied,  is  a  constituent  in  all  the  rocks 
above  mentioned,  and  besides,  is  an  essential  part  of  the 
atmosphere  and  water ;  it  is  the  most  universally  diffused  of 
the  elements.  It  is  united  with  hydrogen  in  the  constitu- 
tion of  water,  and  with  nitrogen  in  the  constitution  of  the 
atmosphere.  Chlorine  combined  with  sodium  constitutes 
common  salt,  which  occurs  in  sea  water  and  brine  springs, 
and  is  also  found  in  vast  beds  in  some  rock  strata. 

It  is  thus  seen  how  few  are  the  elements  essential  to  the 
framework  of  our  globe.  The  various  metallic  ores,  of  less 
general  diffusion,  are  however  of  vast  economical  importance 
to  man,  and  multiply  considerably  the  number  of  mineral 
species.  Those  important  to  the  general  student,  however, 
are  comparatively  few.  The  whole  number  of  well  estab- 
lished species  in  the  mineral  kingdom  is  about  500  ;  of  these, 
more  than  two-thirds  are  known  only  to  the  mineralogist- 
It  is  the  province  of  chemistry  to  discuss  fully  the  nature 
of  the  elements,  and  their  modes  of  combination*  It  is  suf- 
ficient to  add  here,  for  the  benefit  of  any  who  may  not  have 
the  requisite  elementary  chemical  knowledge,  how  the  chem- 
ical names  of  minerals  indicate  their  composition.  Terms 
such  as  oxyd  of  iron,  chlorid  of  iron,  express  a  combination 
of  iron  with  the  element  oxygen,  or  chlorine  ;  so  also  sul- 
phuret  of  iron  is  a  compound  of  iron  with  sulphur.  The 
force  of  the  terminations  id  or  uret  is  always  as  here  ex- 
plained. Protoxyd  and  peroxyd  imply  different  proportions 

Which  are  the  next  most  common  ingredients  of  rocks  1  Mention 
the  other  ingredients  alluded  to.  What  is  an  oxyd  1  a  chlorid  ?  a  «il- 
phuret  ?  a  carbonate  ? 

7 


74  CLASSIFICATION   OF    MINERALS* 

of  oxygen,  the  latter  the  highest.  Terms  such  as  carbonate 
of  lime,  sulphate  of  lime,  indicate  that  the  substance  is  com- 
posed of  an  acid — carbonic  acid,  or  sulphuric  acid  in  the 
instances  cited,  with  lime.  So  silicate  of  soda  is  a  com- 
pound of  soda  and  silicic  acid  (or  silica) ;  and  all  such  com- 
pounds are  theoretically  said  to  consist  of  an  acid  and  a  base — • 
lime  and  soda,  in  the  cases  mentioned,  being  bases. 

The  true  foundation  of  a  species  in  mineralogy  must  be 
derived  from  crystallization^  as  the  crystallizing  force  is  funda- 
mental in  its  nature  and  origin  ;  and  it  is  now  generally  admit- 
ted that  identity  of  crystalline  form  and  structure  is  evidence 
of  identity  of  species.  This  principle  unites  certain  distinct 
chemical  compounds  into  the  same  species  : — for  example,  a 
silicate  of  magnesia  and  a  silicate  of  iron  crystallizing  alike, 
constitute  but  one  species  in  mineralogy,  though  chemically 
so  different.  Oxyd  of  iron  and  magnesia  are  themselves 
nearly  identical  in  molecular  form  and  size,  and  on  this  fact 
depends  their  power  of  replacing  one  another  even  in  com- 
plex  compounds.  They  are  therefore  said  to  be  isomorphous 
(from  the  Greek  isos,  similar,  and  morpfte,  form.) 

There  are  many  groups  of  these  isomorphous  substances!, 
and  some  knowledge  of  them  is  necessary  to  enable  the 
reader  to  understand  why  different  varieties  of  a  mineral 
species  may  differ  so  widely,  as  they  often  do,  in  composition. 
Some  of  these  groups  are  as  follows  : 

1.  Alumina,  peroxyd  of  iron,  peroxyd  of  manganese. 

2.  Lime,  magnesia,  protoxyds  of  iron,  manganese  and  zinc. 

3.  Baryta,  strontia,  oxyd  of  lead. 

4.  Sulphur,  selenium,  tellurium. 

5.  Tungsten,  molydenum. 

6.  Phosphoric  acid,  arsenic  acid. 

In  cpidota  the  alumina  may  be  replaced  by  peroxyd  of 
iron  or  manganese,  and  the  magnesia  in  part  or  wholly  by 
lime,  or  the  protoxyds  of  iron  or  manganese.  The  same  is 
true  of  garnet  and  several  other  minerals.  The  rhombohe- 
drons  of  carbonate  of  lime,  carbonate  of  iron,  and  carbonate 
of  magnesia,  are  very  nearly  identical  in  angle,  because  the 
bases  are  ismorphous.  This  subject  is  illustrated  by  the 
greater  part  of  mineral  species. 

What  is  a  sulphate  ?  a  silicate  ?  What  is  the  test  of  identity  of 
species  in  mineralogy?  What  are  isomorphous  substances?  What 
are  the  common  groups  of  isomorphous  substances  in  minerals  ?  Ex- 
plain by  examples. 


CLASSIFICATION    OF    MINERALS.  75 


GENERAL    VIEW    OF    THE    CLASSIFICATION    OF    MINERALS. 

The  classification  adopted  in  this  work  is  based  on  the 
constitution  of  minerals.  The  following  is  a  general  view 
of  it: 

CLASS  I.  Gases  :  consisting  of  or  containing  nitrogen  or 
hydrogen. 

CLASS  IJ.     Water. 

CLASS  III.    .Carbon,  and  compounds  of  carbon. 

CLASS  IV.     Sulphur. 

CLASS  V.  Haloid  minerals  :  compounds  of  the  alkalies 
and  earths,  with  the  soluble  acids  (sulphuric,  nitric,  carbonic, 
&c.  or  water,)  or  of  their  metals  with  chlorine  or  fluorine.' 
1,  Salts  of  ammonia  ;  2,  of  potash^  3,  of  soda  ;  4,  of  baryta; 
5,  of  strontia  ;  6,  of  lime  ;  7,  of  magnesia  ;  8,  of  alumina. 

CLASS  VI.  Earthy  minerals  :  silica  and  siliceous  or  alu- 
minous compounds  of  the  alkalies  and  earths — 1,  silica ;  2, 
Hme ;  3,  magnesia  ;  4,  alumina  ;  5,  glucina ;  6,  zirconia ; 
7,  thoria. 

CLASS  VII.  Metals  and  metallic  ores,  (exclusive  of  the 
metals  of  the  alkalies  and  earths)  :  1,  Metals  easily  oxydiz- 
able — cerium,  yttrium,  uranium,  iron,  manganese,  chromium, 
nickel,  cobalt,  zinc,  cadmium,  bismuth,  lead,  mercury,  copper, 
titanium,  tin,  molybdenum,  tungsten,  tellurium,  antimony, 
arsenic ;  2,  Noble  metals :  platinum,  indium,  palladium,  gold, 
silver. 


Explain  the  classification  •adopted. 


GASEOUS   MINERALS. 


CLASS  I.— GASES. 

The  gases  occurring  native  are  as  follows  :  1.  containing 
or  consisting  of  nitrogen  :  atmospheric  air,  nitrogen.  2. 
containing  hydrogen :  carbureted  hydrogen,  phosphureted 
hydrogen,  sulphureted  hydrogen,  muriatic  acid.  3.  contain- 
ing carbon  or  sulphur :  carbonic  acid,  sulphurous  acid. 

ATMOSPHERIC    AIR. 

1.  Atmospheric  air  is  the  air  we  breathe.  It  consists  of 
oxygen  21  per  cent,  by  weight,  and  nitrogen  79  per  cent., 
with  a  small  proportion  of  carbonic  acid.  It  has  neither  color, 
odor,  nor  taste.  It  supports  life  and  combustion  through  the 
oxygen  which  it  contains,  this  gas  being  used  or  absorbed 
in  respiration  as  well  as  in  the  burning  of  wood  or  a  candle. 
The  oxygen  thus  consumed  is  restored  to  the  air  again  by 
vegetation  which  gives  out  oxygen  through  the  day,  and  in 
this  way  the  quality  of  the  atmosphere  requisite  for  life  is 
sustained.  It  is  about  815  times  lighter  than  water,  and 
11,065  times  lighter  than  mercury.  A  hundred  cubic  inches 
weigh  about  31  grains. 

NITROGEN    GAS. 

Nitrogen  destroys  life,  and  has  neither  color,  odor  nor 
taste.  It  is  one  of  the  constituents  of  the  atmosphere.  It 
bubbles  up  through  the  waters  of  many  springs,  having  been 
derived  from  air  by  some  decompositions  in  progress  within 
the  earth,  by  which  the  oxygen  of  the  air  is  absorbed. 

Lebanon  springs  in  Columbia  county,  New  York,  and  a 
region  in  the  town  of  Hoosic,  Rensselaer  county,  afford 
large  quantities  of  this  gas.  There  is  another  locality  at 
Canoga,  Seneca  county,  where  the  water  is  in  violent  ebul- 
lition from  the  escape  of  the  gas  ;  its  temperature  is  40  F* 
There  are  other  nitrogen  springs  in  Virginia,  west  of  the 
Blue  Ridge  at  Warm  and  Hot  Springs  ;  in  Buncombe- 
county,  N.  C. ;  and  on  the  Washita  in  Arkansas.  At  Bath,  in 
England,  nitrogen  is  escaping  from  the  tepid  springs  at  the 

What  gases  occur  in  nature  1  What  is  the  constitution  of  the  at- 
mosphere? its  general  characters?  the  weight?  What  is  said  of  th& 
characters  of  nitrogen1?  Where  does  nitrogen  occur  in  nature  1 


- 

GASES    CONTAINING    HYDROGEN.  77 

rate  of  267  cubic  inches  a  minute,  or  222  cubic  feet  a  day. 
The  gas  from  these  nitrogen  springs  contains  only  2  or  3 
per  cent,  of  oxygen,  and  often  a  very  little  carbonic  acid. 

CARBURETED    HYDROGEN. 

Carbureted  hydrogen  consists  of  carbon  75,  hydrogen  25; 
burns  with  a  bright  yellow  flame.  It  is  the  same  gas  nearly 
that  is  used  for  lighting  the  streets  in  some  of  our  cities.  It 
issues  abundantly  from  some  coal  beds  and  beds  of  bitumi- 
nous slate.  At  Fredonia,  in  western  New  York,  near  Lake 
Erie,  it  is  given  out  so  freely  from  a  slate  rock,  that  it  is 
used  for  lighting  the  village.  A  vessel  containing  220  cubic 
feet  is  filled  in  about  15  hours.  A  light-house  at  Portland 
harbor,  on  Lake  Erie,  four  miles  from  Fredonia,  is  also 
lighted  with  the  same  gas  from  other  springs. 

Another  carbureted  hydrogen,  burning  with  a  pale  blue 
flame,  rises  in  bubbles  through  pools  of  water,  owing  to 
vegetable  decomposition  in  the  soil  beneath. 

PHOSPHURETED    HYDROGEN. 

Phosphureted  hydrogen  consists  of  phosphorus  91*29,  and 
hydrogen  8'71.  It  takes  fire  spontaneously.  The  phos- 
phoric matter,  called  Jack-o'-lantern,  sometimes  seen  float- 
ing over  marshy  places,  is  supposed  to  be  phosphureted 
hydrogen. 

SULPHURETED    HYDROGEN. 

Sulphureted  hydrogen  consists  of  sulphur  94'2,  hydrogen 
5*8.  It  has  the  odor  and  taste  of  putrescent  eggs  and  burns 
with  a  bluish  flame. .  It  is  abundant  about  sulphur  springs, 
issuing  freely  from  the  waters,  as  in  western  New  York  and 
in  Virginia.  It  is  sometimes  found  about  volcanoes.  It 
blackens  silver  and  also  a  common  cosmetic  made  of  oxyd 
of  bismuth. 

MURIATIC  ACID. — Hydrochloric  Acid. 

Muriatic  acid  gas  consists  of  hydrogen  2*74,  chlorine 
97*26.  It  has  a  very  pungent  odor  and  is  acrid  to  the  skin. 

What  is  the  composition  of  carbureted  hydrogen  1  its  general  charac- 
ters ?  mode  of  occurrence  in  nature  1  What  is  said  of  Fredonia  1 
Mention  the  characters  of  phosphureted  hydrogen  ;  the  characters  of 
eulphureted  hydrogen ;  its  mode  of  occurrence.  What  is  said  of  muri- 
atic acid  ? 

7* 


78  WATER. 

It  is  rapidly  dissolved  by  water.  If  passed  into  a  solution 
of  nitrate  of  silver,  it  produces  a  white  precipitate  which 
soon  blackens  on  exposure.  It  is  given  out  occasionally  by 
volcanoes.* 

CLASS  IL— WATER. 

Water  (oxyd  of  hydrogen)  is  the  well  known  liquid  of  our 
streams  and  wells.  The  purest  natural  water  is  obtained  by 
melting  snow,  or  receiving  rain  in  a  clean  glass  vessel ;  but 
it  is  absolutely  pure  only  when  procured  by  distillation.  It 
consists  of  hydrogen  1  part  by  weight,  and  oxygen  8  parts. 
It  becomes  solid  at  3*2°  Fahrenheit,  (or  0°  Centigrade)  and 
then  crystallizes,  and  constitutes  ice  or  snow.  Flakes  of 
snow  consist  of  a  congeries  of  minute  crys- 
tals, and  stars  like  the  annexed  figure  may 
often  be  detected  with  a  glass.  Various 
other  allied  forms  are  also  assumed.  The 
rays  meet  at  an  angle  of  60°,  and  the 
branchlets  pass  off  at  the  same  angle  with 
^^  perfect  regularity.  The  density  of  water  is 

greatest  at  39°  1  F. ;  below  this  it  expands  as  it  approaches 
32°,  owing  to  incipient  crystallization.  It  boils  at  212  F. 
A  cubic  inch  of  pure  water  at  60°  F.  and  30  inches  of  the 
barometer,  weighs  252*458  grains.  A  pint,  United  States 
standard  measure,  holds  just  7342  troy  grains  of  water, 
which  is  little  above  a  pound  avoirdupois  (7000  grains  troy.) 
Water  as  it  occurs  on  the  earth,  contains  some  atmos- 
pheric air,  without  which  the  best  would  be  unpalatable. 
This  air,  with  some  free  oxygen  also  present,  is  necessary 
to  the  life  of  water  animals.  In  most  spring  water  there 
is  a  minute  proportion  of  salts  of  lime,  (sulphate,  chlorid 
or  carbonate,)  often  with  a  trace  of  common  salt,  carbo- 
nate of  magnesia  and  some  alumina,  iron,  silica,  phospho- 
ric acid,  carbonic  acid,  and  certain  vegetable  acids.  These 
impurities  constitute  usually  from  TV  to  10  parts,  in  10,000 
parts  by  weight.  The  Long  Pond  water,  used  in  Boston, 

Of  what  does  water  consist  ?  What  is  said  of  snow  and  ice  ?  What 
of  the  density  of  water  1  its  boiling  temperature  ]  the  weight  of  a  pint  1 
What  are  the  usual  impurities  of  common  spring  or  river  water  I 

*  Carbonic  acid  and  sulphurous  acid  gases,  are  described,  one  under 
carton,  and  the  other  under  sulphur. 


GASES    CONTAINING    HYDROGEN.  79 

contains  about  £  a  part  in  10,000  ;  the  Sch'.iylkill  of  Phila- 
delphia, about  1  part  in  10,000;  the  Crotoa,  used  in  New 
York  city,  1  to  1£  parts  in  10,000.  In  the  Schuylkill 
water  the  constituents  of  the  1  part  of  solid  ingredients  were, 
chlorid  of  sodium  1'47,  chlorid  of  magnesium  0'094,  sulphate 
of  magnesia  0*57,  silica  0'8,  carbonate  of  lime  18'72,  car- 
bonate of  magnesia  3*51,  carbonate  of  soda  and  loss  16'44.* 
The  water  towards  the  surface  is  always  purer  than  that 
below. 

Sea  water  contains  32  to  37  parts  of  solid  substances  in 
solution  in  1000  parts  of  water.  The  largest  amount  in  the 
Atlantic,  36*6  pails,  is  found  under  the  equator,  away  from  the 
land  or  the  vicinity  of  fresh  water  streams  ;  and  the  smallest 
in  narrow  straits,  as  Dover  Straits  where  there  are  only  32*5 
parts.  In  the  Baltic  and  the  Black  Sea,  the  proportion  is 
only  one-third  that  in  the  open  ocean.  Of  the  whole,  one- 
half  to  two-thirds  is  common  salt  (chlorid  of  sodium.)  The 
other  ingredients  are  magnesian  salts,  (chlorid  and  sulphate,) 
amounting  to  four-fifths  of  the  remainder,  with  sulphate  and 
carbonate  of  lime,  and  traces  of  bromids,  iodids,  phosphates 
and  fluorids.  The  water  of  the  British  channel  affords,  water 
964-7  parts  in  1000,  chlorid  of  sodium  27-1,  chlorid  of  pot- 
assium 0'8,  chlorid  of  magnesium  3*7,  sulphate  of  magnesia 
2-30,  sulphate  of  lime  1*4,  carbonate  of  lime  0*03,  with  some 
bromid  of  magnesium,  and  probably  traces  of  iodids,  fluorids 
and  phosphates.  The  bitter  taste  of  sea  water  is  owing  to 
thfe  salts  of  magnesia  present. 

The  waters  of  the  Dead  Sea  contain  200  to  250  parts  of 
solid  matter  in  1000  parts,  (or  20  to  25  per  cent.,)  including 
7  to  JO  per  cent,  of  common  salt,  the  same  proportion  of 
magnesian  salts  principally  the  chlorid,  2^  to  3^  per  cent, 
of  carbonate  and  sulphate  of  lime,  besides  some  bromids  and 
alumina.  The  density  of  these  waters  is  owing  to  this  large 
proportion  of  saline  ingredients.  The  brine  springs  of  New 
York  and  other  states  south  and  west,  are  well  known 
sources  of  salt,  (see  beyond  under  common  salt.)  Many  of  the 
springs  afford  bromine,  and  large  quantities  of  it  are  manufac- 
tured for  making  daguerreotype  plates  and  other  purposes. 

What  proportion  of  solid  substances  in  sea  water,  and  of  this  what 
proportion  is  common  salt  ?  What  proportion  magnesian  salts  ?  What 
is  the  bitter  taste  of  sea  water  owing  to  ? 

*  Chem.  Exam,  by  B.  Sillunan.  Jr.,  Jour.  Sci.,  ii  ser.,  ii,  218. 


80  CARBON. 

Mineral  waters  vary  much  in  constitution.  They  often 
contain  carbonate  of  iron,  like  those  of  Saratoga  and  Balls- 
town,  and  are  then  called  chalybeate  waters,  from  the  ancient 
name  for  iron  or  steel,  cJialybs,  derived  from  the  name  of  a 
country  on  the  Baltic.  The  water  of  Congress  Spring,  ac- 
cording to  Dr.  Steel,  contains  in  a  pint,  chlorid  of  sodium 
48*1,  bicarbonate  of  magnesia  1 2 '0,  carbonate  of  lime  12*3, 
carbonate  of  iron  0'6,  silica  0'2,  iodid  of  sodium  nearly  0.5, 
with  a  trace  of  bromid  of  potash  ;  of  carbonic  acid  39*0  cubic 
inches  and  nearly  1  cubic  inch  of  atmospheric  air. 

Minute  traces  of  salts  of  zinc  and  arsenic,  lead,  copper, 
antimony  and  tin,  have  been  found  in  some  waters.  What- 
ever  is  soluble  in  a  region  through  which  waters  flow,  will  of 
course  be  taken  up  by  them,  and  many  ingredients  are 
soluble  in  minute  proportions,  which  are  usually  described 
as  insoluble. 


CLASS  III.— CARBON  AND  COMPOUNDS  OF 
CARBON. 

Carbon  occurs  crystallized  in  the  diamond.  In  a  massive 
form,  and  more  or  less  pure  state,  it  constitutes  the  various 
kinds  of  mineral  coal.  Combined  with  hydrogen,  or  hydro- 
gen  and  oxygen,  it  forms  bitumen,  amber,  and  a  number  of 
native  mineral  resins. 

DIAMOND. 

Monometric.  In  octahedrons,  dodecahedrons  and  more 
complex  forms.  Faces  often  curved,  as  in  the  annexed 
figures.  Cleavage  octahedral ;  highly  perfect. 

1234 


Color  white  or  colorless  ;    also  yellowish,   red,  orange, 

What  are  chalybeate  waters  ?  What  is  the  difference  between  the 
diamond  and  charcoal  1  What  is  the  crystallization  of  the  diamond  1 
What  other  characters  are  mentioned  ? 


THE    DIAMOND.  81 

green,  brown  or  black.  Luster  adamantine.  Transparent; 
translucent  when  dark  colored.  H  =  10.  Gr  =  3*48 — 
3-55. 

Composition.  Pure  carbon.  It  burns  and  is  consumed  at 
-a  high  temperature,  producing  carbonic  acid  gas.  Exhibits 
vitreous  electricity  when  rubbed.  Some  specimens  exposed 
to  the  sun  for  a  while,  give  out  light  when  carried  to  a  dark 
place.  Strongly  refracts  and  disperses  light. 

Dif.  Diamonds  are  distinguished  by  their  superior  hard- 
ness  ;  their  brilliant  reflection  of  light  and  adamantine  luster ; 
their  vitreous  electricity  when  rubbed,  which  is  not  afforded 
by  other  gems  unless  they  are  polished  ;  and  by  the  prac- 
ticed ear,  by  means  of  the  sound  when  rubbed  together. 

Obs.  Diamonds  occur  in  India,  in  the  district  between 
Golconda  and  Masulipatam,  and  near  Parma,  in  Bundel- 
cund,  where  some  of  the  most  magnificent  specimens  have 
been  found  ;  also  on  the  Mahanuddy,  in  Ellore.  In  Borneo, 
they  are  obtained  on  .the  west  side  of  the  Ratoos  mountain, 
with  gold  and  platina.  The  Brazilian  mines  were  first  dis- 
covered in  1728,  in  the  district  of  Serra  do  Frio,  to  the  north 
of  Rio  de  Janeiro  ;  the  most  celebrated  are  on  the  river 
Jequitinhonha,  which  is  called  the  Diamond  river,  and  the 
Rio  Pardo  ;  twenty-five  to  thirty  thousand  carats  are  export- 
ed annually  to  Europe  from  these  regions.  In  the  Urals  of 
Russia  they  had  not  been  detected  till  July,  1829,  when 
Humboldt  and  Rose  were  on  their  journey  to  Siberia.  The 
river  Gunil,  in  the  province  of  Constantine,  in  Africa,  is  re- 
ported to  have  afforded  some  diamonds.  In  the  United 
States,  the  diamond  has  been  met  with,  in  Rutherford  county, 
North  Carolina,  (fig.  4,)  and  Hall  county,  Georgia. 

The  original  rock  in  Brazil  appears  to  be  either  a  kind  of 
laminated  granular  quartz  called  itacolumite  ;  or  a  ferruginous 
quartzose  conglomerate.  The  itacolumite  occurs  in  the  Urals, 
and  diamonds  have  been  found  in  it ;  and  it  is  also  abundant 
in  Georgia  and  North  Carolina.  In  India,  the  rock  is  a 
quartzose  conglomerate.  The  origin  of  the  diamond  has 
been  a  subject  of  speculation,  and  it  is  the  prevalent  opinion 
that  the  carbon,  like  that  of  coal,  is  of  vegetable  origin. 
Some  crystals  have  been  found  with  black  uncry stall ized 
particles  or  seams  within,  looking  like  coal  ;  and  this  fact 
has  been  supposed  to  prove  their  vegetable  origin. 

How  is  the  diamond  distinguished  ?     What  are  its  principal  localities  ? 


82  CARBON. 

Diamonds  with  few  exceptions  are  obtained  from  alluvial 
washings.  In  Brazil,  the  sands  and  pebbles  of  the  diamond 
rivers  and  brooks  (the  waters  of  which  are  drawn  off  in  the 
dry  season  to  allow  of  the  work)  are  collected  and  washed 
under  a  shed,  by  a  stream  of  water  passing  through  a  suc- 
cession of  boxes.  A  negro  washer  stands  by  each  box,  and 
inspectors  are  stationed  at  intervals.  When  a  diamond  is 
found  weighing  17|  carats,  the  negro  is  entitled  to  his 
liberty. 

The  largest  diamond  of  which  we  have  any  knowledge  is 
mentioned  by  Travernier,  as  in  the  possession  of  the  Great 
Mogul.  It  weighed  originally  900  carats,  or  2769*3  grains, 
but  was  reduced  by  cutting  to  861  grains.  It  has  the  form 
and  size  of  half  of  a  hen's  egg.  It  was  found  in  1550,  in  the 
mine  of  Colone.  The  diamond  which  formed  the  eye  of  a 
Braminican  idol,  and  was  purchased  by  the  Empress  Catha- 
rine II.  of  Russia  from  a  French  grenadier  who  had  stolen 
it,  weighs  193  carats,  and  is  as  large,  as  a  pigeon's  egg. 
The  Pitt  or  regent  diamond  is  of  less  size,  it  weighing  but 
136'25  carats,  or  41 9^  grains;  but  on  account  of  its  un- 
blemished transparency  and  color,  it  is  considered  the  most 
splendid  of  Indian  diamonds.  It  was  sold  to  the  Duke  of 
Orleans  by  Mr.  Pitt,  an  English  gentleman,  who  was  gover- 
nor of  Bencolen,  in  Sumatra,  for  £130,000.  It  is  cut  in  the 
form  of  a  brilliant,  and  is  estimated  at  £125,000.  Napoleon 
placed  it  in  the  hilt  of  his  sword  of  state.  The  Rajah  of 
Mattan  has  in  his  possession  a  diamond  from  Borneo,  weigh- 
ing 367  carats. 

The  diamonds  of  Brazil  are  seldom  large.  Maure  men- 
tions one  of  120  carats,  but  they  rarely  exceed  18  or  20. 
The  famous  diamond,  weighing  1680  carats,  belonging  to 
the  emperor  of  Brazil,  is  supposed  to  be  a  topaz. 

Diamonds  are  valued  according  to  their  color,  transpa- 
rency and  size.  When  limpid  (of  pure  water)  and  no  ex- 
traordinary magnitude,  the  value  of  a  wrought  diamond  is 
estimated  by  first  ascertaining  the  weight  in  carats.*  The 

How  are  diamonds  obtained  1     How  are  diamonds  valued  ? 

*  A  carat  is  a  conventional  weight,  and  is  divided  into  4  grains, 
which  are  a  little  lighter  than  4  grains  troy  ;  74  1-16  carat  grains  are 
equal  to  72  troy  grains.  The  term  carat  is  derived  from  the  name  of 
a  bean  in  Africa,  which,  in  a  dried  state,  has  long  been  used  in  that 
country  for  weighing  gold.  These  beans  "were  early  carried  to  India, 
and  were  employed  there  for  weighing  diamonds. 


THE    DIAMOND.  83 

rule  given  is  as  follows :  double  the  weight  in  carats,  and 
multiply  the  square  of  the  product  by  £2.  Thus  a  wrought 
diamond  weighing  1  carat,  would  be  worth  £8  ;  one  of  4 
carats,  £128;  one  of  10  carats,  £800.  Above  20  carats, 
the  prices  rise  much  more  rapidly.  A  flaw,  however  mi- 
nute,  or  the  slightest  smokmess,  diminishes  very  much  the 
value.  The  average  price  of  rough  diamonds,  of  first 
quality,  of  1  carat,  is  £2;  of  2  carats,  £8,  since  it  loses 
half  its  weight  in  cutting,  and  becomes  then  one  of  1  carat 
wrought. 

The  rule  just  given  is  scarcely  regarded  in  market,  as 
so  much  depends  upon  the  purity  of  water.  In  different 
countries,  moreover,  the  standard  of  taste  as  regards  dia- 
monds is  very  different,  the  market  in  England  demanding 
the  very  first  quality,  while  in  other  countries  a  somewhat 
inferior  kind  satisfies  the  purchaser. 

The  rose  diamond  is  more  valuable  than  a  snow-white 
diamond,  owing  to  the  great  beauty  of  its  color  and  its  rarity. 
The  green,  diamond  is  much  esteemed  on  account  of  its 
color.  The  blue  is  prized  only  for  its  rarity,  as  the  color  is 
seldom  pure.  The  black  diamond,  which  is  uncommonly 
rare  and  without  beauty,  is  highly  prized  by  collectors.  The 
brown,  gray  and  yellow  varieties  are  of  much  less  value  than 
the  pure  white  or  limpid  diamond. 

The  diamond  is  cut  by  taking  advantage  of  its  cleavage, 
and  also  by  abrasion  with  its  own  powder  and  by  friction 
with  another  diamond.  The  flaws  are  first  removed  by 
cleaving  it ;  or  else  by  sawing  it  with  an  iron  wire,  which  is 
covered  with  diamond  powder — a  tedious  process,  as  the 
wire  is  generally  cut  through  after  drawing  it  across  five  or 
six  times.  After  the  portion  containing  flaws  has  thus  been 
cut  off,  the  crystal  is  fixed  to  the  end  of  a  stick,  in  a  strong 
cement,  leaving  the  part  projecting  which  is  to  be  cut ;  and 
another  being  prepared  in  the  same  manner,  the  two  are 
rubbed  together  till  a  facet  is  produced.  By  changing  the 
position,  other  facets  are  added  in  succession  till  the  required 
form  is  obtained.  A  circular  plate  of  soft  iron  is  then  charged 
with  the  powder  produced  by  the  abrasion,  and  this,  by  its 
revolution,  finally  polishes  the  stone.  To  complete  a  single 
facet  often  requires  several  hours.  Diamonds  were  first  cut 
in  Europe,  in  1456,  by  Louis  Berquen,  a  citizen  of  Bruges; 

How  are  diamonds  cut  1 


84  CARBON* 

but  in  China  and  India,  the  art  of  cutting  appears  to  have 
been  known  at  a  very  early  period. 

By  the  above  process,  diamonds  are  cut  into  brilliant,  rose 
and  table  diamonds.  The  brilliant  has  a  crown  or  upper 
part,  consisting  of  a  large  central  eight-sided  facet,  and  a 
series  of  facets  around  it ;  and  a  collet,  or  lower  part,  of  pyr» 
amidal  shape,  consisting  of  a  series  of  facets,  with  a  smaller 
series  near  the  base  of  the  crown.  The  depth  of  a  brilliant 
is  nearly  equal  to  its  breadth,  and  it  therefore  requires  a 
thick  stone.  Thinner  stones,  in  proportion  to  the  breadth, 
are  cut  into  rose  and  table  diamonds.  The  surface  of  the 
rose  diamond  consists  of  a  central  eight-sided  facet  of  small 
size,  eight  triangles,  one  corresponding  to  each  side  of  the 
table,  eight  trapeziums  next,  and  then  a  series  of  sixteen  tri- 
angles. The  collet  side  consists  of  a  minute  central  octagon, 
surrounded  by  eight  trapeziums,  corresponding  to  the  angles 
of  the  octagon,  each  of  which  trapeziums  is  subdivided  by  a 
salient  angle  into  one  irregular  pentagon  and  two  triangles. 
The  table  is  the  least  beautiful  mode  of  cutting,  and  is  used 
for  such  fragments  as  are  quite  thin  in  proportion  to  the 
breadth.  It  has  a  square  central  facet,  surrounded  by  two 
or  more  series  of  four-sided  facets,  corresponding  to  the  sides 
of  the  square. 

Diamonds  have  also  been  cut  with  figures  upon  them.  As 
early  as  1500,  Charadossa  cut  the  figure  of  one  of  the 
Fathers  of  the  church  on  a  diamond,  for  Pope  Julius  II. 

Diamonds  are  employed  for  cutting  glass;  and  for  this 
purpose  only  the  natural  edges  of  crystals  can  be  used,  and 
those  with  curved  faces  are  much  the  best.  Diamond  dust 
is  used  to  charge  metal  plates  of  various  kinds  for  jewelers, 
lapidaries  and  others.  Those  diamonds  that  are  unfit  for 
working,  are  sold  for  various  purposes,  under  the  name  of 
bort.  Fine  drills  are  made  of  small  splinters  of  bort,  which 
are  used  for  drilling  other  gems,  and  also  for  piercing  holes 
in  artificial  teeth  and  vitreous  substances  generally. 

The  diamond  is  also  used  for  lenses  for  microscopes. 
When  ground  plano-convex,  they  have  but  slight  chromatic 
aberration,  and  consequently  a  larger  field,  and  but  little  loss 
of  light,  compared  with  similar  lenses  of  other  materials. 
They  often  have  an  irregularity  of  structure  when  perfectly 


What  are  the  three  forms  usually  given  the  diamond  1    For  what 
purposes  are  diamonds  used  1 


MINERAL  COAL.  85 

p-^ir-H   wMch  nnfit*  thorn  for  this  purpose,  and  such  lenses 
therefore  are  seldom  made. 

MINERAL  COAL. 

Massive.  Color  black  or  brown,  opaque.  Brittle  or 
sectile.  H  =  1—2-5.  Gr  =  1-2—1  '75. 

Composition.  Carbon,  with  usually  a  few  per  cent,  of 
silica  and  alumina,  and  sometimes  oxyd  of  iron ;  often  con- 
tains a  large  proportion  of  bitumen.  The  bituminous  varie- 
ties burn  with  a  bright  flame  and  bituminous  odor  ;  while 
those  destitute  of  bitumen  afford  only  a  pale  blue  flame, 
arising  from  the  decomposition  of  the  water  present  and  the 
formation  of  the  gas  called  carbonic  oxyd. 

VARIETIES. — 1.   Without  bitumen. 

Anthracite.  Anthracite  (called  also  glance  coal  and  stone 
coal)  has  a  high  luster,  and  is  often  iridescent.  It  is  quite 
compact  and  hard,  and  has  a  specific  gravity  from  1-3  to 
1'75.  It  usually  contains  80  to  90  percent,  of  carbon,  with 
4  to  7  of  water,  the  rest  consisting  of  earthy  impurities. 
There  is  often  some  bitumen  present,  in  which  case  it  burns 
with  considerable  flame. 

Besides  the  use  of  anthracite  for  fuel,  it  is  often  made  into 
inkstands,  small  boxes,  and  other  articles,  which  have  a  high 
polish,  and  fine  specimens  of  this  kind  of  ware  may  be  ob- 
tained in  Philadelphia. 

2.  Bituminous  varieties. 

Bituminous  coal  varies  much  and  indefinitely  in  the 
amount  of  bitumen  it  contains,  and  there  is  a  gradual  pas- 
sage in  its  varieties  into  varieties  of  anthracite.  It  is  softer 
than  anthracite  and  less  lustrous.  The  specific  gravity  does 
not  exceed  1'5. 

Pitching  or  caking  roaZ,  as  it  is  distinguished  in  England, 
at  first  breaks  when  heated,  into  small  pieces,  which,  on 
raising  the  heat,  again  unite  into  a  solid  mass.  Its  color  is 
velvet  or  grayish  black.  It  burns  readily  with  a  lively  yel- 
low flame,  but  requires  frequent  stirring  to  prevent  its  caking, 
and  so  clogging  the  fire.  The  principal  beds  at  Newcastle, 
England,  afford  this  kind  of  coal.  Clierry  coal  resembles 
pitch  coal  in  appearance,  but  does  not  soften  and  cake.  It 

Of  what  does  mineral  coal  consist  1  How  does  anthracite  differ 
from  other  varieties  ? 

8 


63  CARBON. 


is  very  brittle,  and  in  mining  there  is  consequently  much 
waste.  It  burns  with  a  clear  yellow  flame.  It  occurs  at 
the  Glasgow  coal  beds,  and  is  named  from  its  luster  and 
beauty.  The  splint  coal  (or  hard  coal)  of  the  same  region 
is  harder  than  the  cherry  coal. 

Cannel  coal  is  very  compact  and  even  in  texture,  with 
little  luster,  and  breaks  with  a  large  conchoidal  fracture.  It 
takes  fire  readily,  and  burns  without  melting  with  a  clear 
yellow  flame,  and  has  hence  been  used  as  candles — whence 
the  name.  It  is  often  made  into  inkstands,  snuff-boxes  and 
other  similar  articles. 

Brown  coal,  wood  coal,  lignite,  are  names  of  a  less  perfect 
variety  of  coal,  usually  having  a  brownish  black  color,  and 
burning  with  an  empyreumatic  odor.  It  has  often  the  struc- 
ture of  the  original  wood.  The  term  brown  coal  is,  how- 
ever, applied  generally  to  any  coal  more  recent  in  origin 
than  the  era  of  the  great  coal  beds  of  the  world,  although  it 
may  not  have  any  distinct  remains  of  a  woody  structure,  or 
burn  with  an  empyreumatic  odor.  The  name  lignite  has 
sometimes  the  same  general  application,  though  without 
strict  propriety. 

Jet  resembles  cannel  coal,  but  is  harder,  of  a  deeper  black 
color,  and  has  a  much  higher  luster.  It  receives  a  brilliant 
polish,  and  is  set  in  jewelry.  It  is  the  Gagates  of  Dioscor- 
ides  and  Pliny,  a  name  derived  from  the  river  Gagas,  in 
Syria,  near  the  mouth  of  which  it  was  found,  and  the  origin 
of  the  term  jet,  now  in  use. 

Obs.  Mineral  coal  occurs  in  extensive  beds  or  layers, 
interstratified  with  different  rock  strata.  The  associate 
rocks  are  usually  clay  shales  (or  slaty  beds)  and  sandstones  ; 
and  the  sandstones  are  occasionally  coarse  grit  rocks. 
There  are  sometimes  also  beds  of  limestone  alternating  with 
the  other  deposits.  In  a  vertical  section  through  the  coal 
measures — as  the  series  of  rocks  and  coal  seams  are  usually 
called — there  may  be  below,  sandstones  and  shales  in  alter- 
nating  layers,  or  sandstones  alone  and  then  shales;  there 
may  next  appear  upon  the  shale  a  bed  or  layer  of  coal,  one, 
two  or  even  thirty  feet  thick  ;  then  above  the  coal,  other 
layers  of  shale  and  sandstone ;  and  then  another  layer  of 
coal ;  again  shale  and  sandstones  in  various  alternations,  or 


What  is  cannel  coal  ]  brown  coal  or  lignite  1  jet  ]     How  do  beds  of 
coal  occur,  and  what  are  the  associated  rocks  ? 


MINERAL    COAL.  87 

perhaps  layers  of  limestone;  and  then  a  third  bed  of  coal, 
and  so  on.  By  such  alternations  the  series  is  completed. 
Immediately  in  the  vicinity  of  the  coal,  the  rock  is  generally 
rather  a  shale  than  a  sandstone,  and  these  shales  are  usually 
full  of  impressions  of  leaves  and  stems  of  plants.  The  clay 
shales  are  sometimes  quite  soft  and  earthy,  and  of  a  light 
clay  color ;  but  in  most  coal  regions  they  are  hard  and  firm, 
with  a  brownish  or  black  color,  in  the  vicinity  of  the  coal 
layer.  The  sandstones  are  either  of  a  grayish,  bluish,  or 
reddish  color. 

These  various  layers  constituting  coal  beds,  are  some- 
times nearly  or  quite  horizontal  in  position,  as  in  New  Hol- 
land and  west  of  the  Appalachians.  They  are  very  often 
much  tilted,  dipping  at  various  angles  and  sometimes  verti- 
cal, as  is  generally  the  case  throughout  central  Pennsylvania  ; 
an*!  in  some  cases  the  beds  are  raised  in  immense  folds,  as 
the  leaves  of  a  book  may  be  folded,  by  a  side  wise  pressure. 
They  are  very  commonly  intersected  by  fractures,  along 
which  the  coal  seam  on  one  side  is  higher  or  lower  than  on 
the  other,  owing  to  a  dislocation,  (then  said  to  be  faulted)  ; 
and  miners  working  in  a  bed  for  a  while,  in  such  a  case, 
find  it  to  terminate  abruptly,  and  have  to  explore  above  or 
below  for  its  continuation.  These  are  points  of  great  im- 
portance in  the  mining  of  coal. 

There  is  no  infallible  indication  of  the  presence  of  coal 
distinguishable  in  the  mineral  nature  of  rocks  ;  for  just  such 
rocks  as  are  here  described  occur  where  no  coal  is  to  be 
found,  and  where  none  is  to  be  expected.  The  presence  of 
fossil  leaves  of  ferns,  and  of  plants  having  jointed  stems  or  a 
scarred  or  embossed  surface,  in  the  shales  or  sandstone,  is  a 
useful  hint ;  the  discovery  of  the  coal  itself  a  much  better 
one.  The  geologist  ascertains  the  absence  of  coal  from  a 
region  by  examining  the  fossils  in  the  rocks ;  these  fossils 
being  different  in  rocks  of  different  ages,  they  indicate,  at 
once  whether  the  beds  under  investigation  belong  to  what  is 
called  the  coal  series.  If  they  contain  certain  trilobites, 
and  other  species  which  are  found  only  in  more  ancient 
rocks,  there  is  no  longer  a  doubt  that  coal  is  not  to  be  ob- 
tained in  any  workable  quantities ;  and  he  arrives  at  the 
same  conclusion  if  the  remains  are  those  of  more  recent 


What  is  said  of  the  position  of  the  beds  1     How  do  the  rocks  indicate 
whether  coal  is  to  be  expected  in  a  region  or  not  ? 


88  CARBON. 

rocks,  such  as  fossil  fish  of  certain  genera,  or  the  remains  or 
traces  of  birds  or  quadrupeds,  or  of  such  species  of  shells  as 
never  occur  as  low  in  the  rocks  as  true  coal  beds.  But  if 
the  fossils  are  such  as  have  been  described  as  characterizing 
a  coal  series,  there  is  then  reason  for  exploration.  It  is 
impossible  in  this  place  to  give  such  knowledge  as  will  be 
practically  useful.  The  inquirer  must  refer  to  treatises  on 
geology,  or  better  to  the  practical  geologist,  whose  judgment 
in  such  questions  might  often  have  saved  much  useless 
mining  and  wasted  expenditure. 

Mineral  coal  is  very  widely  distributed  over  the  world. 
England,  France,  Spain,  Portugal,  Belgium,  Germany,  Aus- 
tria, Sweden,  Poland  and  Russia,  have  their  beds  of  mineral, 
coal.  It  is  also  abundant  in  India,  China,  Madagascar,  Van 
Dieman's  Land,  Borneo  and  other  East  India  Islands,  New 
Holland,  and  at  Conception  in  Chili.  But  no  where  is  the 
coal  formation  more  extensively  displayed  than  in  the  United 
States,  and  in  no  part  of  the  world  are  its  beds  of  greater 
thickness,  more  convenient  for  working,  or  more  valuable  in 
quality.  There  are  four  extensive  areas  occupied  by  this 
formation.  One  of  these  areas  commences  on  the  north,  in 
Pennsylvania  and  southeastern  Ohio,  and  sweeping  south 
over  western  Virginia  and  eastern  Kentucky  and  Tennessee, 
to  the  west  of  the  Apalachians,  or  partly  involved  in  their 
ridges,  it  continues  to  Alabama  near  Tuscaloosa,  where  a 
bed  of  coal  has  been  opened.  It  has  been  estimated  to  cover 
63,000  square  miles.  It  embraces  several  isolated  patches 
in  the  eastern  half  of  Pennsylvania.  A  second  coal  area  (the 
Illinois)  lies  adjoining  the  Mississippi,  and  covers  the  larger 
part  of  Illinois,  the  western  part  of  Indiana,  and  a  small 
northwest  part  of  Kentucky;  it  is  but  little  smaller  than  the 
preceding.  A  third  occupies  a  portion  of  Missouri  west  of 
the  Mississippi.  A  fourth  covers  the  central  portion  of 
Michigan.  Besides  these,  there  is  a  smaller  coal  region  (a 
fifth)  in  Rhode  Island,  which  appears  near  Portsmouth,  not 
far  from  the  railroad  to  Boston,  and  also  in  Mansfield,  Massa- 
chusetts. Out  of  the  borders  of  the  United  States,  on  the 
northeast,  commences  a  sixth  coal  area,  that  of  Nova  Scotia 
and  New  Brunswick,  which  covers  10,000  square  miles, 


What  is  said  of  the  distribution  of  coal  over  the  globe  ?  How  many 
coal  areas  are  there  in  the  United  States,  and  what  their  positions? 
What  is  said  of  ihe  Nova  Scotia  and  New  Brunswick  coal  beds  I 


MINERAL    COAL. 


89 


2500  square  miles  of  which  are  in  Nova  Scotia.  At  Cape 
Breton  is  still  another  field  of  coal. 

The  coal  of  Rhode  Island  and  eastern  Pennsylvania  is 
anthracite.  Going  west  in  Pennsylvania,  the  anthracite 
becomes  more  and  more  bituminous  ;  and  at  Pittsburg,  at  its 
western  extremity,  as  also  throughout  the  western  states,  it 
is  wholly  of  the  bituminous  kind.  The  Rhode  Island  variety 
is  so  hard  and  compact  and  free  from  all  volatile  ingredients, 
that  for  many  years  it  had  been  deemed  unfit  for  use.  The 
anthracite  of  eastern  Pennsylvania  affords  3  to  6  per  cent, 
of  aqueous  vapor,  and  1  to  4  per  cent,  of  volatile  combustible 
matter.  In  the  Bradford  coal  field,  lying  near  the  eastern 
limits  of  the  bituminous  coal  deposits,  Prof.  Johnson  obtained 
1  to  8  per  cent,  of  moisture,  9  to  15  per  cent,  of  inconden- 
sable gas,  5  to  17  of  earthy  matter,  and  62  to  75  of  carbon. 
In  the  bituminous  coal  of  the  Portage  railroad,  Cambria 
county,  Penn.,  he  obtained  18-2  per  cent,  of  volatile  com- 
bustible  matter  ;  in  that  of  Caseyville,  Ky.,  and  Cannelton, 
Indiana,  30  to  34  per  cent. ;  and  in  a  coal  from  Osage  river, 
Missouri,  41-35  per  cent.  The  general  fact  that  the  pro- 
portion  of  bitumen  increases  as  we  go  westward,  is  here  well 
exhibited. 

Some  of  these  results,  derived  from  an  extensive  series  of 
experiments,  are  thus  averaged  by  Prof.  Johnson  : 


Moisture. 

Vol.  Combustible<  Ashes  and 
Hatter.         \  Clinker. 

Fixed 
Carbon. 

Pennsylvania  anthra- 

134 

384 

7-37 

87-45 

cites, 

Maryland  free  burn- 
ing bituminous  coal 

125 

1580 

9-94 

7301 

Pennsylvania      free    i 

burning  bituminous  > 
coal,                           ) 

0-82 

1701 

1335 

68-82 

Virginia  bituminous, 

1  64 

36-63 

10-74 

50-99 

Cannelton,    Indiana, 
bituminous, 

220 

3399 

4-97 

58:44 

It  has  also  been  shown  that  this  fact  is  connected  with  the 
geological  condition  of  the  country,  the  anthracite  occurring 
in  the  east  wrhere  the  rocks  are  variously  uplifted  and  thrown 
out  of  position  by  subterranean  forces,  evincing  also  other 


What  is  the  relative  geographical  position  of  the  anthracite  and  bitu- 
minous coal  in  the  United  States  ?  What  has  probably  made  the  dif- 
ference in  these  two  kinds  of  coal  1 

8* 


90  CARBOX. 

effects  of  heat  besides  this  debituminisation  of  the  coal ; 
while  the  bituminous  coal  occurs  where  such  disturbances  of 
the  rocks  have  not  taken  place  :  and  the  amount  of  bitumen 
increases  as  we  recede  from  the  region  of  greatest  distur- 
bance. The  heat  and  attendant  siliceous  solutions  have 
therefore  been  the  means  of  giving  unusual  hardness  to  the 
Rhode  Island  coal. 

Owing  to  the  various  upliftings  or  foldings  of  the  strata  and 
subsequent  denudations,  the  beds  are  often  exposed  to  view 
in  the  sides  of  hills  or  ridges,  and  the  coal  in  Pennsylvania  is 
in  most  cases  rather  quarried  out  than  mined.  The  layers 
are  at  times  20  to  35  feet  thick,  without  any  slaty  seams,  and 
the  excavations  appear  like  immense  caverns,  whose  roofs 
are  supported  by  enormous  columns  of  coal,  "  into  which  a 
coach  and  six  might  be  driven  and  turned  again  with  ease." 

Besides  the  great  coal  beds  of  the  coal  era,  as  it  is  signifi- 
cantly called,  there  are  small  beds,  sometimes  workable,  of 
a  more  recent  date.  The  bed  near  Richmond,  Va.,  belongs 
to  a  subsequent  period ;  there  are  also  beds  in  Yorkshire, 
and  at  Brora  in  Sutherland.  Tertiary  coal  occurs  in 
Provence,  and  also  in  Oregon  on  the  Cowlitz.  These  beds 
of  more  recent  coals  are  seldom  sufficiently  extensive  to  pay 
for  working,  and  are  often  much  contaminated  by  pyrites. 

The  amount  of  anthracite  worked  in  1820,  in  Pennsylvania, 
was  only  380  tons;  in  1847,  it  amounted  to  more  than 
3,000,000  tons  ;  and  the  whole  amount  of  both  anthracite 
and  bituminous  coal  worked  in  that  state,  in  1847,  was  not 
Jess  than  5,000,000  tons.  In  Great  Britain,  the  annual 
amount  of  coal  mined  is  about  35,000,000  of  tons. 

The  uses  of  mineral  coal  are  well  known.  The  Pennsyl- 
vania anthracite  was  first  introduced  into  blacksmithing  in 
1768  or  1769,  by  Judge  Obadiah  Gore,  a  blacksmith,  who 
early  left  Connecticut  for  Wilkesbarre.  It  is  now  employed 
in  smelting  iron  ores,  and  for  nearly  every  purpose  in  the 
arts  for  which  charcoal  was  before  employed. 

The  formation  of  coke  from  pit  coal,  for  smelting  iron,  is 
done  in  close  furnaces  or  ovens.  After  heating  up,  the  coal 
(about  two  tons)  is  thrown  in  at  a  circular  opening  at  top, 
and  remains  for  48  hours  ;  the  doorway  is  gradually  closed 
to  shut  off  the  air  as  the  combustion  increases,  and  finally 
the  atmosphere  is  wholly  shut  off,  and  in  this  condition  it 


How  is  coke  prepared  ? 


GRAPHITE.  91 

remains  for  12  hours.  The  volatile  matter  is  thus  expelled, 
and  the  cokes  produced  are  ponderous,  extremely  hard,  of  a 
light  gray  color,  and  having  a  metallic  luster.  To  make 
another  kind  of  coke,  like  charcoal,  the  pit  coal  is  placed  in 
a  receptacle  more  like  a  baker's  oven,  and  the  air  has 
more  free  access.  Both  of  these  kinds  of  coke  are  used  in 
smelting. 

GRAPHITE. — Plumbago. 

Occasionally  in  six-sided  prisms,  with  a  transversely  foli- 
ated structure.  Usually  foliated,  and  massive  ;  also  granu- 
lar and  compact- 
Luster  metallic,  and  color  iron  black  to  dark  steel  gray. 
Thin  laminae  flexible.  H  =  l — 2.  Gr  =  2'09.  Soils  paper, 
and  feels  greasy. 

Composition.  90  to  96  per  cent,  of  carbon,  with  the  rest 
iron.  Some  specimens  from  Brazil  contain  scarcely  a  trace 
of  iron.  It  is  often  called  carburet  of  iron,  but  is  not  a 
chemical  compound.  It  is  infusible  before  the  blowpipe, 
both  alone  and  with  reagents  ;  it  is  not  acted  upon  by  acids. 
Dif.  Resembles  molybdenite,  but  diners  in  being  unaf- 
fected by  the  blowpipe  and  acids.  The  same  characters 
distinguish  the  granular  varieties  from  any  metallic  ores 
they  resemble. 

Obs.  Graphite  (called  also  black  lead)  is  found  in  crys. 
talline  rocks,  especially  in  gneiss,  mica  slate  and  granular 
limestone ;  also  in  granite  and  argillite,  and  rarely  in  green, 
stone.  Its  principal  English  locality  is  at  Borrowdale,  in 
Cumberland,  lire  observes  that  this  mineral  became  so 
common  a  subject  of  robbery,  a  century  ago,  as  to  hate  en- 
riched many  living  in  the  neighborhood  ;  a  body  of  miners 
would  break  into  the  mine  and  hold  possession  of  it  for  a 
considerable  time.  The  place  is  now  protected  by  a  strong 
building,  and  the  workmen  are  required  to  put  on  a  working 
dress  in  an  apartment  on  going  in  and  take  it  off  on  coming 
out.  In  an  inner  room  two  men  are  seated  at  a  large  table 
assorting  and  dressing  the  graphite,  who  are  locked  in  while 
at  work  and  watched  by  the  steward  from  an  adjoining  room, 
who  is  armed  with  two  loaded  blunderbusses.  This  is 
deemed  necessary  to  check  the  pilfering  spirit  of  the  Cum- 

What  is  the  appearance  of  graphite  ?  What  is  its  prominent  char- 
acteristic ?  its  composition  1  Where  does  it  occur  ?  Where  is  it  worked 
in  England  ? 


92  GRAPHITE. 

berland  mountaineers.  In  some  years  the  net  produce  of 
the  six  weeks1  annual  working  of  the  mine,  has  amounted 
to  £40,000. 

In  the  United  States,  graphite  occurs  in  large  masses  in 
veins  in  gneiss  at  Sturbridge,  Mass.  It  is  also  found  in 
North  Brook  field,  Brimfield  and  Hinsdale,  Mass. ;  at  Roger's 
rock,  near  Ticonderoga  ;  near  Fishkill  landing  in  Dutchess 
county  ;  at  Rossie,  in  St.  Lawrence  county,  and  near  Amity, 
in  Orange  county,  N.  Y. ;  at  Greenville,  L.  C. ;  in  Corn- 
wall,  near  the  Housatonic,  and  in  Ashford,  Ct. ;  near  Attle- 
boro,  in  Buck's  county,  Penn.  ;  in  Brandon,  Vermont ;  in 
Wake,  North  Carolina  ;  on  Tyger  river,  and  at  Spartanburg, 
near  the  Cowpens  furnace,  South  Carolina. 

For  the  manufacture  of  pencils  the  granular  graphite  has 
been  preferred,  and  it  is  this  character  of  the  Borrowdale 
graphite  which  has  rendered  it  so  valuable.  At  Sturbridge, 
Mass.,  it  is  rather  coarsely  granular  and  foliated,  and  has 
been  extensively  worked  ;  the  mine  yields  annually  about 
30  tons  of  graphite.  The  mines  of  Ticonderoga  and  Fish- 
kill  landing,  N.  Y.  ;  of  Brandon,  Vt. ;  and  of  Wake,  North 
Carolina,  are  also  worked ;  and  that  of  Ashford,  Ct.,  for- 
merly afforded  a  large  amount  of  graphite,  though  now  the 
works  are  suspended. 

The  material  for  lead  pencils,  when  of  the  finest  quality, 
is  first  calcined  and  then  sawn  up  into  strips  of  the  requisite 
size  and  commonly  set  in  wood,  (usually  cedar,)  as  they  ap- 
pear in  market.  It  is  much  used  now  in  small  cylinders 
without  wood  for  ever-pointed  pencil  cases.  Graphite  of 
coarser  quality,  according  to  a  French  mode,  is  ground  up 
fine  and  calcined,  and  then  mixed  with  the  finest  levigated 
clay,  and  worked  into  a  paste  with  great  care.  It  is  made 
darker  or  lighter  and  of  different  degrees  of  hardness,  by 
varying  the  proportion  of  clay  and  the  degree  of  calcination 
to  which  the  mixture  is  subjected ;  and  the  hardness  is  also 
varied  by  the  use  of  saline  solutions.  Lampblack  is  some- 
times addded  with  the  clay. 

A  superior  method  in  use  at  Taunton,  Mass.,  where  the 
Sturbridge  graphite  is  extensively  employed,  consists  in 
finely  pulverising  it,  and  then  by  a  very  heavy  pressure  ob- 
tained by  machinery,  condensing  it  into  thin  sheets.  These 


How  are  the  best  lead  pencils  made  1     How  are  they  manufactured 
from  the  Sturbridge  bed  ? 


AMBER.  93 

sheets  are  then  sawn  up  of  the  size  required.  The  pencil  is 
pure  graphite,  and  the  foliated  variety  is  preferred  on  account 
of  its  being  freer  from  impurities. 

Graphite  is  extensively  employed  for  diminishing  the 
friction  of  machinery ;  also  for  the  manufacture  of  crucibles 
and  furnaces,  and  as  a  wash  for  giving  a  gloss  to  iron  stoves 
and  railings.  For  crucibles  it  is  mixed  with  half  its  weight 
of  clay. 

CARBONIC    ACID. 

Carbonic  acid  is  the  gas  that  gives  briskness  to  the  Sara- 
toga  and  many  other  mineral  waters,  and  to  artificial  soda 
water.  Its  taste  is  slightly  pungent.  It  extinguishes  com- 
bustion and  destroys  life.  Composition :  carbon  27'65, 
oxygen  72-35. 

Besides  occurring  in  mineral  waters,  it  is  common  about 
some  volcanoes.  The  Grotto  del  Cane  (Dog  cave)  near 
Naples,  is  a  small  cavern  filled  to  the  level  of  the  en- 
trance  with  this  gas.  It  is  a  common  amusement  for  the 
traveler  to  witness  its  effects  upon  a  dog  kept  for  the  purpose. 
He  is  held  in  the  gas  a  while  and  is  then  thrown  out  appa- 
rently lifeless ;  in  a  few  minutes  he  recovers  himself,  picks 
up  his  reward,  a  bit  of  meat,  and  runs  off  as  lively  as  ever. 
If  continued  in  the  carbonic  acid  gas  a  short  time  longer  life 
would  have  been  extinct. 

Carbonic  acid  combined  with  lime  forms  carbonate  of  lime 
or  common  limestone  ;  with  oxyd  of  iron  it  constitutes  spathic 
iron,  one  of  the  common  ores  of  iron  ;  with  oxyd  of  zinc,  it 
forms  calamine,  the  most  profitable  ore  of  zinc.  It  is  found 
in  combination  also  in  various  other  minerals. 

AMBER. 

In  irregular  masses.  Color  yellow,  sometimes  brownish 
or  whitish ;  luster  resinous.  Transparent  to  translucent. 
H  =  2— 2-5.  Gr  =  1-18.  Electric  by  friction. 

Composition.  Carbon  70'7,  hydrogen  11 '6,  oxygen  7*8. 
Burns  with  a  yellow  flame  and  aromatic  odor. 

Obs.  Occurs  in  alluvium  and  on  coasts,  in  masses  from 
a  very  small  size  to  that  of  a  man's  head.  In  the  Royal 
Museum  at  Berlin,  there  is  a  mass  weighing  18  pounds.  On 

For  what  other  purposes  is  it  used  ?  What  is  carbonic  acid  ?  Com- 
bined with  lime,  what  does  it  form  ?  What  is  the  appearance  of  amber  7 
Where  does  it  occur? 


94  MINERAL   RESINS. 


the  Baltic  coast  it  is  most  abundant,  especially  between 
Konigsberg  and  Memel.  It  is  met  with  at  one  place  in  a 
bed  of  bituminous  coal ;  it  also  occurs  on  the  Adriatic,  in 
Poland,  on  the  Sicilian  coast  near  Catania,  in  France  near 
Paris  in  clay,  in  China.  It  has  been  found  in  the  United 
States,  at  Gay  Head,  Martha's  Vineyard,  Camden,  N.  J., 
and  at  Cape  Sable,  near  the  Magothy  river,  in  Maryland. 

It  is  supposed  with  good  reason  to  be  a  vegetable  resin, 
which  has  undergone  some  change  while  inhumed,  a  part  of 
which  is  due  to  acids  of  sulphur  proceeding  from  decompo- 
sing pyrites  or  some  other  source.  It  often  contains  insects, 
and  specimens  of  this  kind  are  so  highly  prized  as  frequently 
to  be  imitated  for  the  shops.  Some  of  the  insects  appear 
evidently  to  have  struggled  after  being  entangled  in  the  then 
viscous  resin,  and  occasionally  a  leg  or  a  wing  is  found  some 
distance  from  the  body,  having  been  detached  in  the  struggle 
for  escape. 

Amber  is  the  elektron  of  the  Greeks  ;  from  its  becoming 
electric  so  readily  when  rubbed,  it  gave  the  name  electricity 
to  science.  It  was  also  called  succinum,  from  the  Greek 
succum,  juice,  because  of  its  supposed  vegetable  origin. 

Uses.  Amber  admits  of  a  good  polish  and  is  used  for  or- 
namental purposes,  though  not  very  much  esteemed,  as  it  is 
wanting  in  hardness  and  brilliancy  of  luster,  and  moreover 
is  easily  imitated.  It  is  much  valued  in  Turkey  for  mouth- 
pieces to  their  pipes. 

Amber  is  the  basis  of  an  excellent  transparent  varnish. 
After  burning,  there  is  left  a  light  carbonaceous  residue,  of 
which  the  finest  black  varnish  is  made.  Amber  affords  by 
distillation  an  oil  called  oil  of  amber,  and  also  succinic  acid  ; 
and  as  the  preparation  of  amber  varnish  requires  that  the 
amber  be  heated  or  fused,  these  products  are  usually  obtained 
at  the  time. 

MINERAL  CAOUTCHOUC. — Elastic  Bitumen. 

In  soft  flexible  masses,  somewhat  resembling  caoutchouc 
or  India  rubber.  Color  brownish  black  ;  sometimes  orange 
red  by  transmitted  light.  Gr  =  0'9 — 1  -25. 

Composition :  carbon  85*5,  hydrogen  13*3.  It  burns 
readily  with  a  yellow  flame  and  bituminous  odor. 

What  is  said  of  the  origin  of  amber]  What  term  has  it  given  to 
science?  For  what  is  amber  used  1  What  is  mineral  caoutchouc  ? 


MINERAL    RESINS.  95 

Obs.  From  a  lead  mine  in  Derbyshire,  England,  and  a 
;oal  mine  at  Montrelais.  It  has  been  found  at  Woodbury, 
tit.,  in  a  bituminous  limestone. 

RETIMTE. — Retinasphaltum. 

In  roundish  masses.  Color  light  yellowish  brown,  green, 
red  ;  luster  earthy  or  slightly  resinous  in  the  fracture.  Sub- 
transparent  to  opaque,  Often  flexible  and  elastic  when  first 
dug  up,  but  loses  these  qualities  on  exposure.  H  =  1 — 2*5. 
Gr  =  1-135. 

Composition :  vegetable  resin  55,  bitumen  41,  earthy 
matter  3.  Takes  fire  in  a  candle  and  burns  with  a  bright 
flame  and  fragrant  odor.  The  whole  is  soluble  in  alcohol 
except  an  unctuous  residue. 

Obs.  Accompanies  Bovey  coal  at  Devonshire ;  also  found 
with  brown  coal  at  Wolchow  in  Moravia,  and  near  Halle. 

BITUMEN. 

Both  solid  and  fluid.  Odor  bituminous.  Luster  resinous  ; 
of  surface  of  fracture  often  brilliant.  Color  black,  brown  or 
reddish  when  solid ;  fluid  varieties  nearly  colorless  and  trans- 
parent. H=0 — 2.  Gr=0-8 — 1-2. 

VARIETIES  : 

Mineral  pitch  or  Asphaltum.  The  massive  variety,  often 
breaking  with  a  high  luster  like  hardened  tar.  The  earthy 
mineral  pitch  includes  less  pure  specimens. 

Petroleum.  A  fluid  bitumen  of  a  dark  color,  which  oozes 
from  certain  rocks  and  becomes  solid  on  exposure.  A  less 
fluid  variety  is  called  maltha,  or  mineral  tar. 

Naphtha,  or  mineral  oil.  A  limpid  or  yellowish  fluid, 
lighter  than  water  ;  specific  gravity  0'7 — 0*84.  It  hardens 
and  changes  to  petroleum  on  exposure.  It  may  be  obtained 
from  petroleum  by  heat,  which  causes  it  to  pass  oflf  in  vapor. 

Composition  of  naphtha :  carbon  82*2,  hydrogen  14'8.  The 
above  varieties  burn  readily  with  flame  and  smoke. 

Obs.  Asphaltum  is  met  with  abundantly  on  the  shores  of 
the  Dead  Sea,  and  in  the  neighborhood  of  the  Caspian.  A 
very  remarkable  locality  occurs  on  the  island  of  Trinidad, 
where  theje  is  a  lake  of  it  about  a  mile  and  half  in  circum- 
ference. The  bitumen  is  solid  and  cold  near  the  shores  ; 
but  gradually  increases  in  temperature  and  softness  towards 

Describe  bitumen.  What  is  asphaltum  ?  petroleum  ?  naphtha  ?  What 
is  said  of  the  asphaltum  of  Trinidad  ? 


96  MINERAL   RESINS* 

the  center,  where  it  is  boiling.  The  appearance  of  tf*a 
solidified  bitumen  is  as  if  the  whole  surface  .had  boiled  up  in 
large  bubbles  and  then  suddenly  cooled.  The  ascent  to  the 
lake  from  the  sea,  a  distance  of  three  quarters  of  a  mile, 
is  covered  with  the  hardened  pitch,  on  which  trees  ami 
vegetation  flourish,  and  here  and  there  about  Poi-nt  La 
Braye,  the  masses  of  pitch  look  like  black  rocks  among  thf 
foliage. 

Large  deposits  of  asphaltum  occur  in  sandstone  in  Albania. 
It  is  also  found  in  Derbyshire,  and  with  quartz  and  fluor  in 
granite  in  Cornwall ;  in  cavities  of  chalcedony  and  calc  spar 
in  Russia  and  other  places. 

Naphtha  issues  from  the  earth  in  large  quantities  in  Persia 
and  the  Birman  empire.  At  Rangoon,  on  one  of  the  branches 
of  the  Irawady  river,  there  are  upwards  of  500  naphtha  and 
petroleum  wells  which  afford  annually  412,000  hogsheads. 
In  the  peninsula  of  Apcheron  on  the  western  shore  of  the 
Caspian,  naphtha  rises  through  a  marly  soil  in  vapor,  and  is 
collected  by  sinking  pits  several  yards  in  depth,  into  which 
the  naphtha  flows.  Near  Amiano  in  the  state  of  Parma,  there 
is  an  abundant  spring. 

In  the  United  States  petroleum  is  common.  The  salines 
of  Kenawha,  Va. ;  Scotsville,  Ky. ;  Oil  creek,  Venango 
county,  Penn.  ;  Duck  creek,  Monroe  county ;  near  Hinsdale 
in  Allegany  county,  N.  Y.,  and  Liverpool,  Ohio,  are  among 
its  localities.  It  was  formerly  collected  for  sale  by  the  Sen- 
eca and  other  Indians ;  the  petroleum  is  therefore  com- 
monly called  Genesee  or  Seneca  oil,  under  which  name  it  is 
sold  in  market. 

Uses.  Bitumen  in  all  its  varieties  was  well  known  to  the 
ancients.  It  is  reported  to  have  been  employed  as  a  cement 
in  the  construction  of  the  walls  of  Babylon.  At  Agrigentum 
it  was  burnt  in  lamps  and  called  Sicilian  oil.  The  Egyp- 
tians made  use  of  it  in  embalming. 

The  asphaltum  of  Trinidad  mixed  with  grease  or  common 
pitch  is  used  for  pitching  (technically,  paying)  the  bottoms 
of  ships  ;  and  it  is  supposed  to  protect  them  from  the  Teredo. 
Two  ship  loads  of  the  pitch  were  sent  to  England  by  Admi- 
ral Cochrane  ;  but  it  was  found  that  the  oil  requited  to  fit  it 
for  use  exceeded  in  expense  the  cost  of  pitch  in  England ; 


Where  is  naphtha  obtained?     What  is  Seneca  oil?     For  what  is 
asphaltum  used  ? 


RESIXS.  9t 

and  consequently  the  project  of  employing  it  in  the  arts  was 
abandoned. 

Asphaltum  is  a  constituent  of  the  kind  of  black  varnish 
called  Japan.  It  is  used  in  France  in  forming  a  cement  for 
covering  the  roofs  and  lining  water  cisterns.  A  limestone, 
thoroughly  dried,  is  ground  up  line  and  stirred  well  in  a  ves- 
sel containing  about  one-fifth  its  weight  of  hot  melted  bitu- 
men. It  is  then  cast  into  rectangular  moulds,  which  are  first 
smeared  with  loam  to  prevent  adhesion.  When  cold,  the 
frame  of  the  mould  is  taken  apart  and  the  block  removed. 

Petroleum  is  used  in  Birmah  as  lamp  oil ;  and  when 
mixed  with  earth  or  ashes,  as  fuel.  Naphtha  affords  both  fuel 
and  light  to  the  inhabitants  of  Batku  on  the  Caspian.  The 
vapor  is  made  to  pass  through  earthen  tubes  and  is  inflamed 
as  it  passes  out  and  used  in  cooking.  The  spring  near 
Amiano  is  used  for  illuminating  the  city  of  Genoa.  Both 
petroleum  and  naphtha  have  been  employed  as  a  lotion  in 
cutaneous  eruptions,  and  as  an  embrocation  in  bruises  and 
rheumatic  affections.  Naphtha  is  often  substituted  for  oil  in  oil 
!  paint,  on  account  of  its  drying  quickly.  It  is  also  employed 
Tor  preserving  the  metals  of  the  alkalies,  potassium  and 
sodium,  which,  owing  to  their  tendency  to  unite  with  oxygen* 
jcannot  be  kept  in  any  liquid  that  contains  this  gas. 

The  petroleum  or  Seneca  oil  of  western  New  York,  Penn- 
isylvania  and  Ohio,  as  it  appears  in  the  market,  is  of  a  dark 
^  brown  color,  and  a  consistency  between  that  of  tar  and 
molasses. 

The  following  are  the  names  of  other  kinds  of  fossil  resin  or  wax : — • 
'.Fossil  Copal,  Middletonite,  Piauzite,  which  are  resinous  and  nearly  or 
wjuite  insoluble  in  alcohol ;  Guyaquillite  and  Berengelite,  from  South 
{America,  resinous  and  soluble  in  alcohol  like  Retinite  ;  Scheererite, 
Hatchetine,  Dysodile,  Hartite,  Ixolyte,  Ozocerite,  Fichtelite,  Konlite, 
'Branchite,  found  with  coal,  especially  brown  coal,  and  resembling  wax 
or  tallow.  Idrialine  is  grayish  or  brownish  black  with  a  grayish  luster, 
'and  occurs  at  the  Cinnabar  mines  of  Idria. 

CLASS  IV.— SULPHUR. 

Sulphur  exists  abundantly  in  the  native  state.  It  occurs 
combined  with  various  metals,  forming  sulphurets  and  sul- 
phates ;  and  the  sulphurets  especially  are  very  common  ores. 
fThe  sulphuret  of  iron  is  common  iron  pyrites ;  sulphuret  of 
copper  is  the  yellow  copper  ore  of  Cornwall  and  other  re- 
gions ;  sulphuret  of  mercury  is  cinnabar,  the  ore  from  which 
9 


NATIVE    SULPHUR. 

mercury  is  mostly  obtained  ;  sulphuret  of  lead  is  galena,  the 
usual  ore  of  lead.  It  is  also  sparingly  met  with  in  the  con- 
dition of  sulphuric  and  sulphurous  acids. 

NATIVE    SULPHUR. 

Trimetric.  In  acute  octahedrons,  and  secon* 
daries  to  this  form,  with  imperfect  octahedral 
cleavage.  Also  massive. 

Color  and  streak  sulphur  yellow,  sometimes 
orange  yellow.  Luster  resinous.  Transparent 
to  translucent.  Brittle.  H  =  1'5 — 2'5.  Gr  = 
2-07. 

Native  sulphur  is  either  pure  or  contaminated  with  clay 
or  bitumen.  It  sometimes  contains  selenium,  and  has  then 
an  orange  yellow  color. 

Dif.  It  is  easily  distinguished  by  burning  with  a  blue 
flame  and  a  sulphur  odor. 

Obs.  The  great  repositories  of  sulphur  are  either  beds 
of  gypsum  and  the  associate  rocks,  or  the  regions  of  active 
or  extinct  volcanoes.  In  the  valley  of  Noto  and  Mazzaro  in 
Sicily,  at  Conil  near  Cadiz  in  Spain,  Bex  in  Switzerland, 
and  Cracow  in  Poland,  it  occurs  in  the  former  situation. 
Sicily  and  the  neighboring  volcanic  islands,  Vesuvius  and 
the  Solfatara  in  its  vicinity,  Iceland,  Teneriffe,  Java,  Hawaii, 
New  Zealand,  Deception  island,  and  most  active  volcanic 
regions  afford  more  or  less  sulphur.  The  native  sulphur  of 
commerce  is  brought  mostly  from  Sicily,  where  it  occurs  in 
beds  along  the  central  part  of  the  south  coast  and  to  some] 
distance  inland.  It  is  often  associated  with  fine  crystals  of 
sulphate  of  strontian.  It  undergoes  rough  purification  by 
fusion  before  exportation,  which  separates  the  earth  and  clay 
with  which  it  occurs.  Sixteen  or  seventeen  thousand  tons 
are  annually  imported  from  Sicily  into  England  alone. 
Sulphur  is  also  exported  from  the  crater  of  Vulcano,  one  of 
the  Lipari  islands,  and  from  the  Solfatara  near  Naples^- 

On  the  Potomac,  25  miles  above  Washington,  fine  speci- 
mens of  sulphur  are  found  associated  with  calc  spar  in  a  gray 
compact  limestone.  Sulphur  is  also  found  as  a  deposit  about 
springs  where  sulphureted  hydrogen  is  evolved,  and  in  cavi- 
ties where  iron  pyrites  have  decomposed.  Localities  of  the 

What  is  the  crystallization  of  sulphur  1  Mention  its  other  characters . 
Where  is  the  sulphur  of  the  arts  obtained? 


NATIVE    SULPHUR.  99 

former  kind  are  common  in  the  state  of  New  York,  and  of 
the  latter  in  the  coal  mines  of  Pennsylvania,  the  gold  rocks 
of  Virginia  and  elsewhere. 

The  sulphur  of  commerce  is  also  largely  obtained  from 
copper  and  iron  pyrites,  it  being  given  off  during  the  roasting 
'  of  these  ores,  and  collected  in  chambers  of  brick  work  con- 
nected with  the  reverberator)'  furnace.  It  is  afterwards 
purified  by  fusion  and  cast  into  sticks. 

Sulphur  when  cooled  from  fusion,  or  above  232°  F.,  crys- 
tallizes in  oblique  rhombic  prisms.  When  poured  into 
water  at  a  temperature  above  300  F.  it  acquires  the  consis- 
tency of  soft  wax,  and  is  used  to  take  impressions  of  gems, 
medals,  &c.,  which  harden  as  the  sulphur  cools. 

The  uses  of  sulphur  for  gunpowder,  bleaching,  the  manu- 
facture of  sulphuric  acid,  and  also  in  medicines,  are  well 
known.  Gunpowder  contains  9  to  20  per  cent. — 9  or  10 
t  per  cent,  for  the  best  shooting  powder,  and  15  to  20  for 
mining  powder. 

SULPHURIC    AND   SULPHUROUS    ACIDS. 

Sulphuric  acid  is  occasionally  met  with  around  volcanoes, 
j  and  it  is  also  formed  from  the  decomposition  of  sulphureted 
hydrogen  about  sulphur  springs.     It  is  intensely  acid.     Com- 
position, sulphur,  40-14,  oxygen  59'86.     It  is  said  to  occur 
in  the  waters  of  Rio  Vinagro,  South  America  ;  also  in  Java, 
I  and  at  Lake  de  Taal  on  Luzon  in  the  East  Indies. 

Sulphurous  acid  is  produced  when  sulphur  burns,  and 
causes  the  odor  perceived  during  the  combustion.  It  is  com- 
mon about  active  volcanoes.  It  destroys  life  and  extinguishes 
combustion.  Composition,  sulphur  50*14,  oxygen  49*86. 

SELENIUM,  ARSENIC.  Selenium  has  close  relations  to  sulphur.  Its 
most  striking  characteristic  is  the  horse-radish  odor  perceived  when  it  ia 
heated.  It  occurs  in  nature  combined  like  sulphur  with  various  metals, 
and  these  ores,  called  seleniets  or  seleniurets,  are  at  once  distinguished 
by  the  odor  when  subjected  to  the  heat  of  the  blowpipe  flame. 

Arsenic  is  also  near  sulphur  in  a  chemical  point  of  view,  although 
metallic  in  luster.  It  forms  similar  compounds  with  the  metals  and 
metallic  oxyds,  which  are  called  arseniurets  and  are  often  highly  im- 
portant ores.  The  arseniurets  of  nickel  and  cobalt  are  the  main  sources 
of  these  metals.  Its  ores  are  distinguished  by  giving  off  when  heated 
an  odor  resembling  garlic. 

What  is  said  of  sulphuric  acid  1     What  is  said  of  sulphurous  acid  7 


100  SALTS    OF    AMMONIA. 


Tellurium  and  Osmium  are  other  metals  having  chemical  relations 
to  sulphur.  They  form  similar  compounds  with  the  metals.  They  are 
of  rare  occurrence. 

The  minerals  containing  the  elements  arsenic,  selenium, tellurium  and 
osmium,  are  described  under  Class  VII,  including  metals  and  metallic 
ores. 

CLASS  V.— HALOID  MINERALS. 

1.    AMMONIA. 
The  salts  of  ammonia  are  more  or  less  soluble,  and  are 
entirely  and  easily  dissipated  in  vapor  before  the  blowpipe. 
By  this  last   character  they  are  distinguished  from  other 
salts. 

SAL  AMMONIAC. — Muriate  of  Ammonia. 

Occurs  in  white  crusts  or  efflorescences,  often 
yellowish  or  gray.  Crystallizes  in  regular 
octahedrons.  Translucent — opaque  ;  taste  sa- 
line and  pungent.  Soluble  in  three  parts  of 
water. 

Composition  :  ammonia  33'89,  chlorine  66'11.  Gives  off 
the  odor  of  hartshorn  when  powdered  and  mixed  with 
quicklime. 

Dif.  Distinguished  by  the  odor  given  off  when  heated 
along  with  quicklime. 

Obs.  Occurs  in  many  volcanic  regions,  as  at  Etna, 
Vesuvius,  and  the  Sandwich  Islands,  where  it  is  a  product 
of  volcanic  action.  Occasionally  found  about  ignited  coal 
seams. 

But  the  sal  ammoniac  of  commerce  is  manufactured 
from  animal  matter  or  coal  soot.  It  is  generally  formed  in 
chimneys  of  both  wood  and  coal  fires.  In  Egypt,  whence 
the  greater  part  of  this  salt  was  formerly  obtained,  the  fires 
of  the  peasantry  are  made  of  the  dung  of  camels ;  and  the 
soot  which  contains  a  considerable  portion  of  the  ammonia- 
cal  salt  is  preserved  and  carried  in  bags  to  the  works,  where 
it  is  obtained  by  sublimation.  Bones  and  other  animal  mat- 
ters are  used  in  France,  and  a  liquor  condensed  from  the  gas 
works,  in  England. 

What  are  general  characters  of  the  salts  of  ammonia  ?     What  is  a 
distinctive  character  of  sal  ammoniac  ?    What  is  its  composition  ?    From 
is  it  manufactured  ?     How  is  it  manufactured  in  Egypt  ? 


SALTS    OF    POTASH NITER.  101 

Uses.  It  is  a  valuable  article  in  medicine,  and  is  em- 
ployed  by  tinmen  in  soldering ;  also,  mixed  with  iron  filings 
or  turnings  to  pack  the  joints  in  steam  apparatus. 

Mascagnine — Sulphate  of  Ammonia.  In  mealy  crusts,  of  a  yellow- 
ish-gray or  lemon-yellow  color.  Translucent.  Taste  pungent  and 
bitter.  Composition,  sulphuric  acid  53'3,  ammonia  22'8,  water  23  9. 
Easily  soluble  in  water.  Occurs  at  Etna,  Vesuvius,  and  the  Lipari  Is- 
lands. It  is  one  of  the  products  from  the  combustion  of  anthracite  coal. 

Phosphate  of  ammonia,  bicarbonate  of  ammonia,  and  phosphate  of 
magnesia  and  ammonia  have  been  found  native  in  guano,  by  E.  F. 
Teschemacher.  The  last  is  named  guanite.  It  occurs  in  brilliant 
rhombic  prisms  of  122°  30'.  Gr=l'5.  H=2. 

Struvite.  A  phosphate  of  ammonia  and  magnesia  like  the  guanite, 
but  containing  13  per  cent,  of  water.  It  occurs  in  yellowish  subtranspa- 
rent  rhombic  crystals.  G=1'7.  H=l.  Slightly  soluble  in  water. 
Found  on  the  site  of  an  old  church  in  Hamburg. 

2.    POTASSA. 

NITER. — Nitrate  of  Potash. 

J 

Trimetric.  In  modified  right  rhombic  prisms.  M  :  M 
about  120°.  Usually  in  thin  white  subtransparent  crusts, 
and  in  needleform  crystals  on  old  walls  and  in  caverns. 
Taste  saline  and  cooling. 

Composition :  potassa  46*56,  nitric  acid  53*44.  Burns 
vividly  on  a  live  coal. 

Dif.  Distinguished  readily  by  its  taste  and  its  vivid 
action  on  a  live  coal ;  and  from  nitrate  of  soda,  which  it  most 
resembles,  by  its  not  becoming  liquid  on  exposure  to  the  air. 

Uses.  Niter,  called  also  saltpeter,  is  employed  in  making 
gunpowder,  forming  75  to  78  per  cent,  in  shooting  powder, 
and  65  in  mining  powder.  The  other  materials  are  sulphur 
(12  to  15  per  cent.)  and  charcoal,  (9  to  12£  for  shooting 
powder,  and  20  for  mining.)  It  is  also  extensively  used  in 
the  manufacture  of  nitric  and  sulphuric  acids  ;  also  for  pyro- 
technic purposes,  fulminating  powders,  and  sparingly  in 
medicine. 

Obs.  Occurs  in  many  of  the  caverns  of  Kentucky  and 
other  Western  States,  scattered  through  the  earth  that  forms 
the  floor  of  the  cave.  In  procuring  it,  the  earth  is  lixiviated, 
and  the  lye,  when  evaporated,  yields  the  saltpeter.  India  is 
its  most  abundant  locality,  where  it  is  obtained  largely  for 

What  does  niter  consist  of?     What  effect  is  produced  when  it  ia 
put  on  a  live  coal  ?     What  are  its  uses?     Where  does  it  occur  ? 
9* 


J02  SALTS    OF    SODA, 

exportation.  It  is  there  used  for  making  a  cooling  mixture  , 
an  ounce  of  powdered  niter  in  five  ounces  of  water  reduces 
the  temperature  15  F. 

Spain  and  Egypt  also  "afford  large  quantities  of  niter  for 
commerce.  This  salt  forms  on  the  ground  in  the  hot  weather 
succeeding  copious  rains,  and  appears  in  silky  tufts  or  efflo- 
rescences ;  these  are  brushed  up  by  a  kind  of  broom,  lixiviated, 
and  after  settling,  evaporated  and  crystallized.  In  France, 
Germany,  Sweden,  Hungary  and  other  countries,  there  are 
artificial  arrangements  called  nitriaries  or  niter-beds,  from 
which  niter  is  obtained  by  the  decomposition  mostly  of  the 
nitrates  of  lime  aud  magnesia  which  form  in  these  beds. 
Refuse  animal  and  vegetable  matter  putrified  in  contact  with 
calcareous  soils  produces  nitrate  of  lime,  which  affords  the 
niter  by  reaction  with  carbonate  of  potash.  Old  plaster 
Jixiviated  affords  about  5  per  cent.  This  last  method  is  much 
used  in  France. 

Chlorid  of  potassium,  or  sylvine,  has  been  observed  with  salt  at 
{Saltzburg. 

3.     SODA. 

The  following  salts  of  soda  are  all  more  or  less  soluble  : 
they  are  in  general  distinguished  by  giving  a  deep  yellow 
light  before  the  blowpipe.  Hardness  below  3  ;  specific 
gravity  below  2*9. 

GLAUBER  SALT. — Sulphate  of  Soda. 

Monoclinate.  In  oblique  rhombic  prisms.  Occurs  in 
efflorescent  crusts  of  a  white  or  yellowish-white  color  ;  also 
in  many  mineral  waters.  Taste  cool,  then  feebly  saline  and 
bitter.  Composition,  soda  1  S'38, sul.acid  24*85,  water 55*77, 

Dif.  It  is  distinguished  from  Epsom  salt,  for  which  it  is 
sometimes  mistaken,  by  its  coarse  crystals,  and  the  yellow 
color  it  gives  to  the  blowpipe  flame. 

Uses.  It  is  used  in  medicine,  and  is  known  by  the  famil- 
iar name  of  "  salts." 

Obs.  On  Hawaii,  one  of  the  Sandwich  Islands,  in  a  cave 
at  Kailua,  glauber  salt  is  abundant,  and  is  constantly  forming. 
It  is  obtained  by  the  natives  and  used  as  medicine.  Glauber 

What  is  a  nitriary  1  What  effect  is  produced  on  the  blowpipe  flame 
by  soda  1  What  is  its  composition  ?  How,  is  it  distinguished  from 
Epsom  salt  1  Where  does  Glauber  salt  occur  native  ? 


CARBONATE    OF  BODJL.  103 

ealt  occurs  also  in  efflorescences  on  the  limestone  below 
.Genesee  Falls,  near  Rochester,  N.  Y,     It  is  also  obtained 
in  Austria,  Hungary  and  elsewhere  in  Europe. 

The  artificial  salt  was  first  discovered  by  a  German 
chemist  by  the  name  of  Glauber.  It  is  usually  prepared  for 
the  arts  from  sea  water. 

NITRATE    OF    SODA. 

Rhombohedral ;  R:  R=106°  33'.  Also  in  crusts  or 
efflorescences,  of  white,  grayish  and  brownish  colors ;  taste 
cooling.  Soluble  and  very  deliquescent, 

Composition :  nitric  acid  €3*40,  soda36-*60 .  Burns  vividly 
on  coal,  with  a  yellow  light. 

Dif.  It  resembles  niter,  (saltpeter,)  but  deliquesces,  and 
gives  a  deep  yellow  light  when  burning. 

Obs.  In  the  district  of  Tarapaca,  the  dry  Pampa  for  an 
extent  of  forty  leagues  is  covered  with  beds  of  this  salt,  mixed 
with  gypsum,  common  salt,  Glauber  salt  and  remains  of 
recent  shells.  The  country  appears  to  have  been  under  the 
sea  at  no  very  remote  period. 

Uses.  It  is  used  extensively  in  the  manufacture  of  nitric 
acid  or  aqua  fortis. 

NATRON. — Carbonate  of  Soda. 

Monoclinate.  Generally  in  white  efflorescent  crusts, 
sometimes  yellowish  or  grayish.  Taste  alkaline.  Effloresces 
on  exposure,  and  the  surface  becomes  white  and  pulverulent. 

Composition :  a  simple  hydrous  carbonate  of  soda.  Effer- 
vesces strongly  with  nitric  acid. 

Dif.  Distinguished  from  other  soda  salts  by  effervescing, 
and  from  Trona,  by  efflorescing  on  exposure. 

Obs.  Abundant  in  the  soda  lakes  of  Egypt,  situated  in  a 
barren  valley  called  Bahr-bela-ma,  about  30  miles  west  of 
the  Delta.  Also  in  lakes  at  Debrezin  in  Hungary ;  in 
Mexico,  north  of  Zacatecas,  and  elsewhere.  Sparingly  dis- 
solved in  the  Seltzer  and  Carlsbad  waters. 

Trona  is  a  sesquicarbonate  of  soda.  In  the  province  of 
Suckena  in  Africa,  between  Tripoli  and  Fezzan,  it  forms  a 


How  does  nitrate  of  soda  differ  in  composition  from  niter?  What 
are  other  peculiarities  distinguishing  it  ?  For  what  is  it  used  ?  Where 
does  it  occur  native  ]  What  are  the  distinctive  characters  of  carbonate 
of  soda  ? 


}04 


SALTS    OF  SODA, 


fibrous  layer  an  inch  thick  beneath  the  soil,  and  several  hunt 
dred  tons  are  collected  annually.     At  a  lake  in  Maracaiboy 
48  miles  from  Merido,  it  is  very  abundant. 

Uses.  Carbonate  of  soda  is  used  extensively  in  the  manu- 
facture of  soap.  The  powders  put  up  for  making  soda  water 
consist  of  this  salt  and  tartaric  acid.  On  mixing  the  two, 
the  tartaric  acid  unites  with  the  soda  and  the  carbonic  acid 
of  the  carbonate  of  soda  escapes  as  a  gas  producing  the  effer- 
vescence. In  Mexico,  this  salt  (or  the  sesquicarbonate, 
trona)  occurs  in  such  abundance  over  extensive  districts  that 
it  is  employed  as  a  flux  in  smelting  ores  of  silver,  especially 
the  chlorid  of  silver  which  is  a  common  ore. 

COMMON    SALT. 

Monometric.     In  cubes  (fig  1)  and  its  secondaries,  as  the 
following.     Sometimes  crystals  have  the  shape  of  a  shallow 
1  234 


cup  like  figure  4,  and  are  called  hopper  shaped  crystals.  They 
were  formed  floating ;  the  cup  receiving  its  enlargement  at 
the  margin,  this  being  the  part  which  lay  at  the  surface  of 
the  brine  where  evaporation  was  going  on.  Common  salt 
is  usually  white  or  grayish,  but  sometimes  presents  rose  red, 
yellow  and  amethystine  tints.  H=2.  Gr= 2-257.  Taste 
saline. 

Composition :  chlorine  60*3,  sodium  39*7.  Crackles  or 
decrepitates  when  heated. 

Dif.  Distinguished  by  its  taste,  solubility,  and  blowpipe 
characters. 

Obs.  Salt  is  usually  associated  with  gypsum,  and  clays  or 
sandstone.  It  occurs  in  extensive  beds  in  Spain,  in  the  Pyre- 
nees, in  the  valley  of  Cardona  and  elsewhere,  forming  hills 
300  to  400  feet  high  ;  in  Poland  at  Wieliczka  ;  at  Hall  in  the 
Tyrol,  and  along  a  range  through  Reichenthal  in  Bavaria, 

For  what  is  it  used  ?  What  happens  when  tartaric  acid  and  carbon- 
ate of  soda  are  mixed  ?  What  are  the  forms  of  crystals  of  common 
salt  ?  Of  what  does  It  consist  1  Where  are  some  of  the  most  remarkable 
deposits  of  rock  salt  ? 


COMMON   SALT.  105 

Hallem  In  Saltzburg,  Hallstadt,  Ischel  and  Ebensee  in  Upper 
Austria,  and  Aussee  in  Stiiia ;  in  Hungary  at  Marmoros  and 
elsewhere  ;  in  Transylvania  ;  Wallaehia,  Gallicia  and  Up- 
per Silesia  ;  at  Vic  and  Dieuze  in  France  ;  at  Bex  in  Swit- 
zerland ;  in  Cheshire,  England  ;  in  northern  Africa  in  vast 
quantities,  forming  hills  and  extended  plains ;  in  northern 
Persia  at  Teflis  ;  in  India  in  the  province  of  Lahore,  and  in 
the  valley  of  Cashmere  ;  in  China  and  Asiatic  Russia  ;  hi 
South  America,  in  Peru  and  the  Cordilleras  of  New  Grenada. 

The  most  remarkable  deposits  vare  those  of  Poland  and 
Hungary.  The  former,  near  Cracow,  has  been  worked 
since  the  year  1251,  and  it  is  calculated  that  there  is  still 
enough  salt  remaining  to  supply  the  whole  worid  for  many 
centuries.  Its  deep  subterranean  regions  are  excavated  into 
houses,  chapels  and  other  ornamental  forms,  the  roof  being 
supported  by  pillars  of  salt ;  and  when  illuminated  by  lamps 
and  torches,  they  are  objects  of  great  splendor. 

The  salt  is  often  impure  with  clay,  and  is  purified  by  dis- 
solving it  in  large  chambers,  drawing  it  off  after  it  has  settled 
and  evaporating  it  again.  The  salt  of  Norwich  (in  Cheshire) 
is  in  masses  5  to  8  feet  in  diameter,  which  are  nearly  pure, 
and  it  is  prepared  for  use  by  crushing  it  between  rollers. 

Beds  of  salt  have  lately  been  opened  in  Virginia  in  Wash- 
ington county,  where  as  usual  it  is  associated  with  gypsum. 
The  Salmon  mountains  of  Oregon  also  afford  rock  salt. 

Salt  beds  occur  in  rocks  of  various  ages :  the  brines  of 
the  United  States  come  from  a  red  sandstone  be  low  the  coal; 
the  beds  of  Norwich,  England,  occur  in  magnesian  lime- 
stone ;  those  of  the  Vosges  in  marly  sandstone  beds  of  the 
lower  secoadaiy ;  that  of  Bex  in  the  lias  or  middle  secondary ; 
that  of  the  Carpathian  Alps  in  the  upper  oolite ;  that  of 
Wieliczka,  Poland  and  the  Pyrenees,  in  the  cretaceous  for- 
mation or  upper  secondary ;  that  of  Catalonia  in  tertiary : 
and  moreover  there  are  vast  deposits  that  are  still  more  re- 
cent, besides  lakes  that  are  now  evaporating  and  producing 
salt  depositions. 

Vast  lakes  of  salt  water  exist  in  many  parts  of  the  world. 
Lake  Timpanogos,  or  Youta,  called  also  the  Great  Salt 
Lake,  has  an  area  of  2000  square  miles,  and  is  remarkable 
for  its  ettent,  considering  that  it  is  situated  towards  the  sum- 


What  is  said  of  the  beds  of  Cracow?     How  is  this  salt  purified? 
Where  do  beds  -occur  in  North  America  ?     What  is  said  of  salt  lakes  t 


106  SALTS    OF  SODA. 

mit  of  the  Rocky  Mountains,  at  an  elevation  of  4200  feel 
above  the  sea.  The  dry  regions  of  these  mountains  and  of 
the  semideserts  of  California  abound  in  salt  licks  and  lakes. 
There  is  a  small  spring  on  the  Bay  of  San  Francisco.  In 
northern  Africa  large  lakes  as  well  as  hills  of  salt  abound, 
and  the  deserts  of  this  region  and  Arabia  abound  in  saline 
efflorescences.  The  Dead  and  Caspian  seas,  and  the  lakes- 
of  Khoordistan,  are  salt.  Over  the  pampas  of  La  Plata  and 
Patagonia  there  are  many  ponds  and  lakes  of  salt  water. 

The  greater  part  of  the  salt  made  in  this  country  is  obtained 
by  evaporation  from  salt  springs.  Those  of  Salina  and 
Syracuse  are  well  known  ;  and  many  nearly  as  valuable  are 
worked  in  Ohio  and  other  western  states.  At  the  best  New 
York  springs  a  bushel  of  salt  is  obtained  from  every  40  gal- 
lons.— (Beck.)  The  springs  of  Onondaga  county,  New  York, 
afforded  in  1841  upwards  of  three  millions  of  bushels  of  salt, 
and  it  is  estimated  that  three  hundred  and  twenty-two  millions 
of  gallons  of  brine  were  raised  and  evaporated  during  that 
year. — (Beck.)  To  obtain  the  brine,  wells  from  50  to  150 
feet  deep  are  sunk  by  boring.  It  is  then  raised  by  machinery, 
carried  by  troughs  to  the  boilers,  which  are  large  iron  kettles 
set  in  brickwork,  and  there  evaporated  by  heat.  As  soon  as 
the  water  begins  to  boil,  the  water  becomes  turbid  from  the 
deposit  of  calcareous  salts  which  are  also  contained  in  salt 
waters,  and  are  less  soluble  than  the  salt.  These  are  re- 
moved with  ladles,  called  bittern  ladles,  with  the  exception 
of  what  adheres  firmly  to  the  sides  of  the  boiler.  The  salt  is 
next  deposited;  it  is  then  collected  and  carried  away  to  drain, 
The  liquid  which  remains  contains  a  large  proportion  of 
nragnesian  salts,  and  is  called  bittern  from  the  bitter  taste  of 
these  salts.  Some  of  the  brine  is  also  evaporated  by  expo- 
sure to  the  sun  in  broad,  shallow  vats. 

This  last  process  is  extensively  employed  in  hot  climates 
for  making  salt  from  sea  water,  which  affords  &  bushel  for 
every  300  or  350  gallons.  For  this  purpose  a  number  of 
large  shallow  basins  are  made  adjoining  the  sea ;  they  have 
a  smooth  bottom  of  clay,  and  all  communicate  with  one  an- 
other. The  water  is  let  in  at  high  tide  and  then  shut  off  foi 
the  evaporation  to  go  on.  This  is  the  simplest  mode,  and  is 

What  is  the  source  of  the  salt  manufactured  in  the  United  States  ? 
How  much  water  is  necessary  to  procure  a  bushel  of  salt  ?  How  is 
the  salt  obtained  from  the  brine  ?  How  much  salt  is  afforded  by  sea 
r,  nnd  how  is  it  obtained  I 


BORAX.  107 

used  even  in  uncivilized  countries,  as  among  the  Pacific 
Islands.  It  is  better  to  have  a  large  receiving  basin  for 
the  salt  water,  which  shall  detain  the  mechanical  impurities 
of  the  water. 

Martinsite  is  a  compound  of  91  per  cent,  of  chlorid  of  sodium  and  9 
of  sulphate  of  magnesia.  It  is  from  the  salines  of  Stassfurth. 

BORAX. — Borate  of  Soda. 

Monoclinate.  In  right  rhomboidal  prisms,  (see  fig.  11, 
page  26)  ;  M  :  T  =  106J  6'.  Cleavage  parallel  with  M  per- 
Feet.  The  crystals  are  white  and  transparent  with  a  glassy 
luster.  H=2 — 2*5.  Gr=  1-716.  Taste  sweetish-alkaline. 

Composition  :  soda  16*37,  boracic  acid  36*53,  water 
47*10.  Swells  up  to  many  times  its  bulk  and  becomes 
opaque  white  before  the  blowpipe,  and  finally  fuses  to  a 
glassy  globule. 

Obs.  Borax  was  originally  brought  from  a  salt  lake  iu 
Thibet,  where  it  is  dug  in  considerable  masses  from  the 
edges  and  shallow  parts  of  the  lakes.  The  holes  thus  made 
in  a  short  time  become  filled  again  with  borax.  The  crude 
borax  was  formerly  sent  to  Europe  under  the  name  oftincal, 
and  there  purified  for  the  arts.  It  has  also  been  found  in 
Peru  and  Ceylon.  It  has  of  late  been  extensively  made 
from  the  boracic  acid  of  the  Tuscany  lagoons  by  the  reaction 
of  this  acid  on  carbonate  of  soda. 

Uses.  Borax  is  used  as  a  flux  not  only  by  the  mineralo- 
gist in  blowpipe  experiments,  but  extensively  in  metallurgi- 
cal operations,  in  the  process  of  soldering,  and  in  the  manu- 
facture of  gems. 

Boracic  acid.  Occurs  in  small  scales,  white  or  yellowish.  Feel 
smooth  and  unctuous.  Taste  acidulous  and  a  little  saline  and  bitter. 
G=l-48.  Composition,  boracic  acid  56'38,  water  43'62.  Fuses  easily 
in  the  flame  of  a  candle,  tinging  the  flame  at  first  green. 

Found  at  the  crater  of  Vulcano,  and  also  at  Sasso  in  Italy,  whence  it 
was  called  Sassolin.  The  hot  vapors  of  the  lagoons  of  Tuscany  afford 
it  in  large  quantities.  The  vapors  are  made  to  pass  through  water, 
which  condenses  them  ;  and  the  water  is  then  evaporated  by  the  steam 
of  the  springs,  and  boracic  acid  obtained  in  large  crystalline  flakes.  It 

What  are  some  of  the  characters  of  borax  1  What  is  its  composition  ? 
What  are  its  effects  before  the  blowpipe  1  What  is  it  used  for  1  Where 
was  it  originally  obtained  1  How  is  it  procured  in  Tuscany  ?  What 
is  boracic  acid  I  What  is  said  of  the  boracic  acid  lagoona  of  Tuscany  ? 


108  SALTS    OP    BARYTA, 

still  requires  purification,  as  the  best  thus  procured  contains  but  50  per 
cent,  of  the  pure  acid. 

It  is  employed  in  the  manufacture  of  borax.  Boron  occurs  in  nature 
also,  in  datholite,  tourmaline  and  borate  of  lime,  but  these  are  not  a 
sufficient  source  to  be  employed  in  the  arts. 

Thenardite.  Thenardite  is  an  anhydrous  sulphate  of  soda  from  Es- 
partine  in  Spain. 

^Gay-Lussite.     Occurs  in   oblong  crystals,  in  a  lake  in  Maracaibo 
S.  A.  ;  it  is  a  hydrous  compound  of  the  carbonates  of  lime  and  soda. 

Glauberite.  In  oblique  cystals,  (usually  flatien-ed,  wish  sharp  edges,) 
nearly  transparent  and  yellowish-gray  in  color.  Taste  weak,  slightly 
saline;  consists  of  49  per  cent,  of  sulphate  of  lime  and  51  of  sulphate  of 
soda.  Occurs  in  rock  salt  at  Villa  Rubia,  Spain,  and  also  at  Aussee  in 
Upper  Austria,  and  Vic  in  France. 

4.     BARYTA. 

The  salts  of  baryta  are  distinguished  by  their  high  specific 
gravity,  which  ranges  from  3*5  to  4'8.  They  resemble  the 
salts  of  strontia,  and  some  of  the  metallic  salts*  From  the 
latter  they  are  distinguished  by  giving  no  odor  nor  metal- 
lic reaction  before  the  blowpipe,  when  pure.  Hardness 
below  4. 

HEAVY  SFAR. — Sulphate  of  Baryta. 

Trimetric.  In  modified  rhombic  and  rectangular  prisms, 
(figs.  1,  2)  M  :  M  =  101°40  ; 
P  :  a  =  141°  10  ;  P  :  cz  =  127D 
18'.  Crystals  usually  tabular. 
Massive  varieties  often  coarse 
lamellar ;  also  columnar,  fibrous,  granular  and  compact. 
Luster  vitreous ;  color  white  and  sometimes  tinged  yellow, 
red,  blue  or  brown.  Transparent  or  translucent.  H  =2*5 — 
3*5.  Gr=4'3 — 4*8.  Some  varieties  are  fetid  when  rubbed. 
Composition  :  sulphuric  acid  34,  baryta  66.  Decrepitates 
before  the  blowpipe  and  fuses  with  difficulty. 

Dif.  Distinguished  by  its  specific  gravity  from  celestine 
and  arragonite,  and  also  by  not  effervescing  with  acids  from 
the  various  carbonates  ;  from  the  metallic  salts,  by  no  metal- 
lic reaction  before  the  blowpipe. 

Obs.     Heavy  spar  is  often  associated  with  the  ores  of 

What  is  a  striking  character  of  the  salts  of  baryta  ?  How  are  they 
distinguished  from  salts  of  the  metals  ?  What  are  the  forms  of  the  crys- 
tals of  heavy  spar  1  What  are  the  colors  ?  What  is  the  composition  ? 


SALTS    OF    BARYTA.  109 

metals.  In  this  way  it  occurs  at  Cheshire,  Conn, ;  Hat- 
n'eld,  Mass.  ;  Rossie  and  Hammond,  New  York ;  Perkio- 
men,  Pennsylvania,  and  the  lead  mines  of  the  west.  At 
Scoharie  and  Pillar  Point,  near  Sackett's  harbor,  are  other 
localities.  Also  near  Fredericksburg  and  elsewhere,  Vir- 
ginia. The  variety  from  Pillar  Point  receives  a  fine  polish 
and  looks  like  marble,  the  colors  being  in  bands  or  clouds. 

Uses.  Heavy  spar  is  ground  up  and  used  as  white  paint, 
and  in  adulterating  white  lead.  When  white  lead  is  mixed 
in  equal  parts  with  sulphate  of  barytes  it  is  sometimes  called 
Venice  white,  and  another  quality  with  twice  its  weight  of 
barytes  is  called  Hamburgh  white,  and  another,  one-third 
white  lead,  is  called  Dutch  white.  When  the  barytes  is  very 
white,  a  proportion  of  it  gives  greater  opacity  to  the  color, 
and  protects  the  lead  from  being  speedily  blackened  by  sul- 
phureous vapors  ;  and  these  mixtures  are  therefore  preferred 
for  certain  kinds  of  painting.  There  are  establishments  for 
grinding  barytes  near  New  Haven,  Ct.,  where  the  spar  from 
Cheshire,  Ct.,  Hatfield,  Mass.,  and  Virginia,  is  used.  The 
iron  ore  or  ferruginous  clay  usually  mixed  with  it,  is  separated 
by  digestion  in  large  vats  of  dilute  sulphuric  acid. 

WITHERITE. — Carbonate  of  Baryta. 

Trimetric.  In  modified  rhombic  prisms,  (fig.  8,  p.  26.) 
M  :  M  =  118°  30';  M  :  e  =  149°  15'.  Also  in  six-sided 
prisms  terminated  with  pyramids.  Cleavage  imper- 
fect. Also  in  globular  or  botryoidal  forms:  often 
massive,  and  either  fibrous  or  granular.  The  mas- 
sive varieties  have  usually  a  yellowish  or  grayish 
white  color,  with  a  luster  a  little  resinous,  and  are 
translucent.  The  crystals  are  often  white  and  nearly  trans- 
parent. H  =3— 3-75.  Gr=4-29— 4-30.  Brittle. 

Composition  :  baryta  77'6,  carbonic  acid  22'4.  Decrep- 
itates before  the  blowpipe  and  fuses  easily  to  a  translucent 
globule,  opaque  on  cooling.  Effervesces  in  nitric  acid. 

Dif.  Distinguished  by  its  specific  gravity  and  fusibility 
from  calcareous  spar  and  arragonite  ;  I  y  its  action  with 
acids  from  allied  minerals  that  are  not  carbonates  ;  by  yield- 
ing no  metal  from  white  lead  ore,  and  by  not  tinging  the 
flame  red,  from  strontianite. 

What  are  the  uses  of  heavy  spar  ?  How  is  witherite  distinguished 
from  other  minerals  ? 

10 


110  SALTS   OF   BARTE*. 

Obs.  The  most  important  foreign  localities  of  witnerife 
are  at  Alstonmoor  in  Cumberland,  and  Anglezark  in  Lan- 
cashire. 

Uses.  This  mineral  is  poisonous,  and  is  used  m  the  north 
of  England  for  killing  rats.  The  salts  of  baryta  are  made 
from  this  species  :  these  safts  are  much  tfsed  rn  chemical 
analysis ;  the  nitrate  affords  a  yellow  light  in  pyrotechny ; 
the  prepared  carbonate  is  a  common  water  color, 

JSarytoealcite  occurs  at  Alstonrooor  ID  CHnj-berland,-  England,  ifi 
whitish  oblique  rhombic  crystals,  M  :  M=106°54'.  H=4.  G=3'6 — 
3'7.  Consists  of  the  carbonates  of  lime  and  baryta. 

Bromlite  is  a  mineral  of  the  same  composition  from  Brom'ley  Hili 
near  Alston,  and  from  Northumberland,  England.  Its  crystals  are  right 
rhombic  prisms. 

Drcelite  is  a  compound  of  the  sulphates  of  baryta  and  lime,  oecurrin-g 
in  small  white  crystals  in  France. 

Sulphato-carbonMc  of  Baryta  occurs  in  six-sided  prisms. 

5.  STRONTIA. 

The  salts  of  strontia  have  a  high  specific  gravity,  it 
ranging  from  8*6  to  4'0r  In  this  respect  they  most  resemble 
the  salts  of  baryta,  and  they  are  distinguished  by  the  same 
characters  as  the  baryta  salts  from  the  salts  of  the  metals, 
Hardness  below  4. 

CHLESTINM. — Sulphate  of  Strontia. 

Trimetric.  In  modified  rhombic  prisms.  M  :  M  =  104° 
to  104°  30'.  Crystals  sometimes  flattened ;  often  long  and 
slender,  a  :  a  =  103°  58'.  Cleavage  distinct 
parallel  with  M.  Massive  varieties  :  columnar 
or  fibrous,  forming  layers  half  an  inch  or  more 
thick  with  a  pearly  luster  ;  rarely  granular. 
Color  generally  a  tinge  of  blue,  but  sometimes  clear  white. 
Luster  vitreous  or  a  little  pearly ;  transparent  to  translucent. 
H  =  3 — 3-5.  Gr  — 3-9 — 4.  Very  brittle. 

Composition :  sulphuric  acid  43*6,  strontia  56'4.  De- 
crepitates before  the  blowpipe,  and  on  charcoal  fuses  rather 
easily  to  a  milk  white  alkaline  globule,  tinging  the  flame 
red.  Phosphoresces  when  heated. 

How  is  witherite  distinguished  from  strontianite  1  What  are  its  uses  ? 
What  is  said  of  the  salts  of  strontia  1  What  is  the  usual  color  and 
appearance  of  celestine  ]  What  is  the  composition  ? 


SALTS   OF   STRONTIA.  HI 

Dif.  The  loiag  slender  crystals  are  distinguished  at  once 
from  heavy  spar,  as  the  lattej-  does  not  occur  in  such  elon- 
gated forms-  From  all  the  varieties  of  heavy  spar,  it  differs 
in  a  lower  specific  gravity  and  blowpipe  characters  ;  from 
the  carbonates  it  is  distinguished  by  not  effervescing  with 
the  acids. 

Ob&.  A  bluish  celestine,  in  long  slender  crystals,  occurs 
at  Strontian  island,  Lake  Erie  ;  Scoharie,  Lockport  and 
Rossie,  N.  Y.,  are  other  localities.  A  handsome  fibrous 
variety  occurs  at  Franktown,  Huntington  county,  Pennsyl- 
vania. Sicily  affords  very  splendid  crystallizations  associ- 
ated with  sulphur  :  the  preceding  figure  represents  one  of  the 
crystals.  The  prisms  are  attached  by  one  end,  and  being 
crowded  over  the  sarface,  they  are  in  beautiful  .contrast  with 
the  yellow  sulphur  beneath. 

The  pale  sky-Hue  tint  so  common  with  the  mineral,  gave 
origin  to  the  name  celestine. 

Uses.  Celestine  i«  used  in  the  arts  for  making  the  nitrate 
of  strontda,  which  is  -employed  for  producing  a  red  color  in 
fire-works.  Celestine  is  changed  to  sulphuret  of  strontium 
by  heating  with  charcoal,  and  then  by  means  of  nitric  acid 
the  nitrate  is  obtained. 

STRONTIAXITJE. — Carbonate  of  Slrontia. 

Trimetric.  In  modified  rhombic  prisms-  M  :  M  =  117° 
19'.  Cleavage  parallel  to  M,  nearly  perfect.  Occurs  also 
fibrous  and  granular,  and  sometimes  in  globular  shapes  with 
a  radiated  structure  within. 

Color  usually  a  light  tinge  of  green;  also  white,  gray  and 
yellowish-brown.  Luster  vitreous,  or  somewhat  resinous. 
Transparent  to  translucent.  H  =  3'5 — 4.  Gr=3*6 — 3'72, 
Brittle. 

Composition :  strontia  7fH,  carbonic  acid  29*9.  Fuses 
before  the  blowpipe  on  thin  edges,  tinging  the  flame  red; 
becomes  alkaline  in  a  strong  heat";  effervesces  with  the 
acids. 

Dif.  Its  effervescence  with  acids  distinguishes  it  from 
minerals  that  are  not  carbonates ;  the  color  of  the  flame  before 
the  blowpipe,  from  wifherite ;  and  this  character  and  the 

For  what  is  celestine  used  1     How  do  strontianite  and  celestine  dif- 
Wtatare distinguishing  charactersof  strontianite  ! 


112 


SALTS    OF    LIME. 


fusibility,  although  difficult,  from  calc  spar.     Calc  spar  s»    *e 
times  reddens  the  flame,  but  not-  so  deeply. 

Obs.  Strontianite  occurs  in  limestone  at  Scoharie,  New 
York,  in  crystals,  and  also  fibrous  and  massive.  Strontian 
in  Argyleshire,  England,  was  the  first  locality  known,  and 
gave  the  name  to  the  mineral  and  the  earth  strontia.  It 
occurs  there  with  galena  in  stellated  and  fibrous  groups  and 
in  crystals. 

Uses.  This  mineral  is  used  for  preparing  the  nitrate  of 
strontia,  which  is  extensively  employed  for  giving  a  red  color 
to  fire-works. 

6.    LIMB. 

With  the  exception  of  the  nitrate  of  lime,  none  of  the 
native  salts  of  lime  are  soluble,  unless  in  minute  propor- 
portions.  They  give  no  odor,  and  no  metallic  reaction  before 
the  blowpipe,  except  such  as  may  arise  from  mixture  with 
iron  or  manganese.  The  specific  gravity  is  below  3*2,  and 
hardness  not  above  5.  The  few  metallic  salts  of  lime 
(arsenate  of  lime,  tungstate  of  lime,  &c.)  are  arranged  with 
the  metallic  ores. 

GYPSUM. — Sulphate  of  Lime. 

1  Monoclinate.     Usually  in  right  rhom- 

boidal  prisms,  with  beveled  sides.  M  : 
T  =  ll  1°14  a  :  a==  143°284;  e  :  e  — 
110°  36'.  Figure  2  represents  a  com- 
mon twin  (or  arrow  head)  crystal.  Emi- 
nently foliated  in  one  direction  and 
cleaving  easily,  affording  laminae  that 
are  flexible  but  not  elastic.  Occurs  also 
in  laminated  masses,  often  of  large  size  ;  in  fibrous  masses, 
with  a  satin  luster ;  in  stellated  or  radiating  forms  consisting 
of  narrow  laminae  ;  also  granular  and  compact. 

When  pure  and  crystallized  it  is  as  clear  and  pellucid  as 
glass,  and  has  a  pearly  luster.  Other  varieties  are  gray, 
yellow,  reddish,  brownish,  and  even  black,  and  opaque. 


Whence  the  name  of  the  mineral  and  earth  strontia?  For  what  is  h 
nsed  ?  What  is  said  of  the  salts  of  lime  1  What  are  the  prominent 
characters  of  gypsum  1 


113 

H=1'5 — :2,  or  so  soft  as  to  be  easily  cut  with  a  knife. 
Gr=2-31 — 2-33.  The  plates  bend  in  one  direction  and  are 
brittle  in  another. 

Composition  ?  lime  32'9,  sulphuric  acid  46*3,  water  20'8. 
Before  the  blowpipe  it  becomes  instantly  white  and  opaque 
and  exfoliates,  and  then  falls  to  powder  or  crumbles  easily  in 
the  fingers.  At  -a  high  heat  h  fuses  with  difficulty.  No 
action  with  acids. 

The  principal  varieties  are  us  follows : 

Selenite,  including  the  transparent  foliated  gypsum,  so 
called  in  allusion  to  its  color  and  luster  from  selene,  the  Greek 
word  for  moon. 

Radiated  gypsum,  having  a  radiated  structure. 

Fibrous  gypsum  or  satin  spar,  white  and  delicately  fibrous. 

Snowy  gypsum  and  alabaster,  including  the  white  or  light- 
colored  compact  gypsum  having  a  very  fine  grain. 

Dif.  The  foliated  gypsum  resembles  some  varieties  of 
Heulandite,  stilbite,  talc  and  mica ;  and  the  fibrous,  looks  like 
fibrous  carbonate  of  lime,  asbestus  and  some  of  the  fibrous 
zeolites  ;  but  gypsum  in  all  its  varieties  is  readily  distin- 
guished by  its  softness  ;  its  becoming  an  opaque  white  powder 
immediately  and  without  fusion  before  the  blowpipe,  and  by 
not  effervescing  nor  gelatinizing  with  acids. 

Obs.  New  York,  near  Lockport,  affords  beautiful  selenite 
and  snowy  gypsum  in  limestone.  At  Camillus  and  Manlius, 
N.  Y,,  and  in  Davidson  county,  Tenn.,  are  other  localities. 
Fine  crystals  of  the  form  represented  in  figure  1,  come  from 
Poland  and  Camfield,  Ohio,  and  large  groups  of  crystals  from 
the  St.  Marys  in  Maryland.  Troy,  N.  Y.,  also  affords  crys- 
tals in  clay.  In  the  mammoth  cave,  Kentucky,  alabaster 
occurs  in  singularly  beautiful  imitation  of  flowers,  leaves, 
shrubbery  and  vines.  Alabaster  comes  mostly  from  Caste- 
lino  in  Italy,  35  miles  from  Leghorn.  Massive  gypsum  oc- 
curs abundantly  in  New  York,  from  Syracuse  westward  to 
the  western  extremity  of  Genesee  county,  accompanying  the 
rocks  which  afford  the  brine  springs ;  also  in  Ohio,  Illinois, 
Virginia,  Tennessee,  Arkansas  and  Nova  Scotia.  It  if 
abundant  also  in  Europe. 

Uses.     Gypsum,  when  burnt  and  ground  up  forms  a  whit 


What  is  the  composition  of  gypsum  1  What  is  alabaster  1  What 
effect  is  produced  by  heat  ?  How  is  gypsum  distinguished  from  talc, 
mica  and  other  minerals  ? 

10* 


114  GYPSUM. 

powder,  which,  after  being  mixed  with  a  little  water,  be- 
comes  on  drying,  hard  and  compact.  This  ground  gypsum 
is  plaster  of  Paris,  and  is  used  for  taking  casts,  making 
models,  and  for  giving  a  hard  finish  to  walls.  Alabaster  is 
cut  into  vases  and  various  ornaments,  statues,  &c.  It  owes 
its  beauty  for  this  purpose  to  its  snowy  whiteness,  translu- 
cency  and  fine  texture.  It  is  moreover  so  soft  as  to  be  cut 
or  carved  with  common  cutting  instruments.  Gypsum  is 
ground  up  and  used  for  improving  soils. 

ANHYDRITE. — Anhyd?'ous  Sulphate  of  Lime. 
Trimetric.     In  rectangular  prisms,  cleaving  easily  in  three 
directions,   and    readily    breaking    into 
square  blocks.    The  figure  is  a  side  view 
of  a  crystal;  M  :  a=I24D  10';  M  :  a  = 
153°  50  ;   M   :   e  =  135°  15'.     Occurs 
also  fibrous  and  lamellar,  often  contort- 
ed; also  coarse  and  fine  granular  and 
compact. 

Color  white  or  tinged  with  gray,  red,  or  blue.  Luster 
more  or  less  pearly.  Transparent  to  subtranslucent.  H  = 
2-5—3-0.  Gr.-=2-9— 3. 

The  crystallized  varieties  have  been  called  muriacite. 
Vulpinite  is  a  siliceous  variety  containing  8  per  cent,  of 
silex,  and  a  little  above  the  usual  hardness,  (3'5.) 

Composition  :  lime  41-5,  sulphuric  acid  58-5.  It  is  a  sul- 
phate of  lime  like  gypsum,  but  differs  in  containing  no  water. 
Whitens  before  the  blowpipe,  but  does  not  exfoliate  like 
gypsum,  and  finally  with  some  difficulty  becomes  covered 
with  a  friable  enamel.  No  action  with  acids. 

Dif*  Differs  from  gypsum  in  being  harder  and  not  ex- 
foliating when  heated ;  from  carbonate  of  lime  and  the 
zeolites  which  it  sometimes  resembles,  in  the  non-action  of 
acids,  and  its  action  before  the  blowpipe.  Its  square  forms  of 
crystallization  and  cleavage  are  also  good  distinguishing 
characters. 

Obs.  A  fine  blue  crystallized  anhydrite  occurs  with  gyp- 
sum and  calcareous  spar  in  a  black  limestone  at  Lock- 
port.  Foreign  localities  are  at  the  salt  mines  of  Bex  in  Swit- 

What  is  plaster  of  Paris,  and  how  is  it  used  ?  For  what  is  alabaster 
used  1  How  is  gypsum  employed  in  agriculture  1  How  does  anhydrite 
differ  in  composition  from  gypsum  ?  Mention  other  distinguishing 
characters. 


CALCAREOUS   SPAR. 


115 


zerland,   at  Hall  in  the  Tyrol,  at  Ischil  in  Upper  Austria, 
Wieliczka  in  Poland  and  elsewhere. 

Uses.     The  vulpinite  variety  is  sometimes  cut  and  polished 
for  ornamental  purposes. 

CALCITE — Calcareous  Spar — Carbonate  of  Lime. 

Rhombohedral,  (fig.  1.)    R  :  R  =  105°  5'.     Cleavage  easy 
parallel  with  the  faces  of  the  fundamentar  rhombohedron. 
1  2  345 


Figure  1,  is  the  fundamental  rhombohedron  ;  figure  2,  is  a 
flat  rhombohedron  with  the  lateral  angles  removed,  sometimes 

'  called  nail-Jiead  spar  ;  figure  3,  is  a  six-sided  prism  ;  figure 
4,  an  acute  rhombohedron  ;  figure  5,  a  scalene  dodecahedron, 

f  the  form  of  the  variety  called  dog-tooth  spar.  Figures  28, 
28a,  30,  31,  page  32  ;  62,  63,  page  39  ;  and  66,  page  40,  are 
other  forms.  Calcareous  spar  also  occurs  fibrous  with  a 

i  silky  luster,  sometimes  lamellar,  and  often  coarse  or  fine 
granular  and  compact. 

The  purest  crystals  are  transparent  with  a  vitreous  luster ; 
the  impure  massive  varieties  are  often  opaque,  and  without 
luster,  or  even  earthy.  The  colors  of  the  crystals  are  either 
white  or  some  light  grayish,  reddish  or  yellowish  tint,  rarely 
deep  red  ;  occasionally  topaz  yellow,  rose  or  violet.  The 
massive  varieties  are  of  various  shades  from  white  to  black, 

•  generally  dull  unless  polished.     H=3.     Gr=2*5 — 2'8. 

Composition:  lime  56-3,  carbonic  acid  43'7  :  sometimes 
impure  from  mixture  with  iron,  silica,  clay,  bitumen  and 
othor  minerals.  Infusible  before  the  blowpipe,  but  gives 
out  an  intense  light,  and  is  ultimately  reduced  to  quicklime. 
Effervesces  with  the  acids.  Many  varieties  phosphoresce 

t  when  heated. 


What  is  the  fundamental  form  of  calcite  or  calc  spar? 
colors  and  appearance  ?     What  is  its  composition  ? 


What  are  its 


116  SALTS    OF   LIME. 

This  species  takes  on  a  great  variety  of  forms  and  colors, 
and  has  received  names  for  the  more  prominent  varieties. 

Iceland  spar. — Transparent  crystalline  calc  spar,  first 
brought  from  Iceland.  Shows  well  double  refraction. 

Satin  spar. — A  finely  fibrous  variety  with  a  satin  luster 
Receives  a  handsome  polish.  Occurs  usually  in  veins 
traversing  rocks  of  different  kinds. 

Chalk. — White  and  earthy,  without  luster,  and  so  soft  as 
to  leave  a  trace  on  a  board.  -Forms  mountain  beds. 

Rock  milk. — White  and  earthy  like  chalk,  but  still  softer, 
and  very  fragile.  It  is  deposited  from  waters  containing 
lime  in  solution. 

Calcareous  tufa. — Formed  by  deposition  from  waters  like 
rock  milk,  but  more  cellular  or  porous  and  not  so  soft. 

Stalactite,  Stalagmite. — The  name  stalactite  is  explained 
on  page  54.  The  deposits  of  the  same  origin  that  cove* 
the  floor  of  a  cavern,  are  called  stalagmite.  They  gen 
erally  consist  of  different  colored  layers,  and  appear  banded 
or  striped  when  broken.  The  so-called  "  Gibraltar  rock'' 
is  stalagmite  from  a  cavern  in  the  rock  of  Gibraltar. 

Limestone  is  a  general  name  for  all  the  massive  varieties? 
occurring  in  extensive  beds. 

Oolite,  Pisolite. — Oolite  is  a  compact  limestone,  consist- 
ing of  small  round  grains,  looking  like  the  spawn  of  a  fish ; 
the  name  is  derived  from  the  Greek  don,  an  egg.  Pisolite,  a 
name  derived  from  pisum,  the  Latin  for  pea,  differs  from 
oolite  in  consisting  of  larger  particles. 

Argentine. — A  white  shining  limestone  consisting  of 
laminae  a  little  waving,  and  containing  a  small  proportion  of 
silica. 

Fontainebleau  limestone. — This  name  is  applied  to  crystals, 
of  the  form  in  figure  4,  containing  a  large  proportion  of  sand, 
and  occurring  in  groups.  They  were  formerly  obtained  at 
Fontainebleau,  France,  but  the  locality  is  exhausted. 

Granular  limestone. — A  limestone  consisting  of  crystal- 
line grains.  It  is  called  also  primary  limestone.  The 
coarser  varieties  when  polished  constitute  the  common  white 
and  clouded  marbles,  and  the  material  of  which  marble 
buildings  are  made.  The  finer  are  used  for  statuary,  and 

What  is  Iceland  spar  ?  What  is  chalk  ?  How  does  satin  spar  under 
this  species  differ  from  that  which  is  a  variety  of  gypsum  ?  What  is 
calcareous  tufa  1  How  are  stalactites  and  stalagmite  formed  ?  What 
is  limestone  1  What  is  oolite  1  What  is  said  of  granular  limestone  ? 


CALCAREOUS    SPAR.  117 


called  statuary  marUe.  The  best  is  as  clear  and  fine  grained 
as  loaf  sugar,  which  it  much  resembles. 

Compact  limestone. — The  common  secondary  limestones, 
breaking  with  a  smooth  surface,  without  any  appearance  of 
grains.  The  rock  is  very  variously  colored,  sometimes  of 
a  uniform  tint,  and  frequently  in  bands,  blotches  or  veinings, 
and  always  nearly  dull  until  polished.  The  varieties  form 
marbles  of  as  many  kinds. 

Stud-stone,  Anthracanite. — A  limestone,  either  columnar 
'or  compact,  which  gives  out  a  fetid  odor  when  struck. 

Plumbocalctte,  from  Cornwall,  contains  2*34  per  cent,  of 
carbonate  of  lead. 

/>//'.  The  varieties  of  this  species  are  easily  distinguished 
by  their  being  scratched  easily  with  a  knife,  in  connection 
with  their  strongly  effervescing  with  acids,  and  their  com- 
plete infusibility.  Calc  spar  is  not  so  hard  as  arragonite, 
and  differs  entirely  in  its  cleavage. 

Obs.  Crystallized  calcareous  spar  occurs  in  magnificent 
forms  in  the  vicinity  of  Rossie,  New  York.  One  crystal 
from  there  now  at  New  Haven  weighs  165  pounds.  Some 
rose  and  purple  varieties  from  this  region  are  very  beautiful. 
Splendid  geodes  of  the  dog-tooth  spar  variety  occur  in  lime- 
stone at  Lockport,  along  with  gypsum  and  pearl  spar.  Ley- 
den  and  Lowville,  N.  Y.,  are  other  localities.  Bergen  Hill, 
N.  J.,  affords  beautiful  wine-yellow  crystals  in  amygdaloid. 
1  Argentine  occurs  near  Williamsburg  and  Southampton,  Mass. 
Rod'  milk  covers  the  sides  of  a  cave  at  Watertown,  N.  Y., 
and  is  now  forming.  Stalactites  of  great  beauty  occur  in 
Weir's  and  other  caves  in  Virginia  and  the  Western  States  ; 
also  in  Ball's  cave  at  Scoharie,  N.  Y.  Chalk  occurs  in 
"England  and  Europe,  but  has  not  been  met  with  in  the  Uni- 

•  'ted  States.     Granular  limestones  are  common  in  the  Eastern 
!;and  Atlantic  States,  and  compact  limestones  in  the  middle 

and  Western,  and  some  beds  of  the  former  afford  excellent 

•  marble  for  building  and  some  of  good  quality  for  statuary. 

Uses.  Any  of  the  varieties  of  this  mineral  when  burnt, 
1  form  quid-lime.  Heat  drives  off  the  carbonic  acid  and  leaves 

•  the  lime  in  a  pure  or  caustic  state.     Some  limestones  con- 
iftain  a  portion  of  clay  disseminated  throughout  it,  and  these 
•;biirn  often   to  hydraulic  lime,  a  kind  of  lime,  of  which  a 


"VVlmt  is  said  of  compact  limestone!     How  is  this  species  distin- 
guu-ned  from  other  species?     What  are  the  uses  oflimestone  ? 


118  SALTS    OF   LIME. 

cement  or  plaster  is  made  that  "  sets"  under  water.     See  - 
further,  the  chapter  on  Rocks,  for  the  uses  of  limestone. 

ARRAGOT\ITE. 

Trimetrie.  In  rhombic  prisms,  (see  fig.  8,  page  26);; 
M  :  M=116°  10'.  Cleavage  parallel  with  M.  Usually. 
in  compound  crystals  having  the  form  of  a  hexagonal  prism, , 
with  uneven  or  striated  sides,  or  in  stellated  forms  consisting; 
of  two  or  three  flat  crystals  crossing  one  another.  Also  inn 
globular  and  coralloidal  shapes ;  also  in  fibrous  seams  in* 
different  rocks. 

Color  white  or  with  light  tinges  of  gray,  yellow,  greens 
and  violet.  Luster  vitreous.  Transparent  to  translucent.. 
H=3-5— 4.  Gr=2-931. 

In  composition^  it  is  identical  with  calcareous  spar,  and  in 
its  action  before  the  blowpipe  it  differs  only  in  falling  to 
powder  readily  when  heated.  Effervesces  also  with  the 
acids.  Phosphoresces  when  heated.  Some  varieties  eon- 
tain  a  few  per  cent,  of  carbonate  of  strontia,  but  this  is  not. 
an  essential  ingredient 

Dif.  The  same  distinctive  characters  as  calcareous  spar, 
except  its  crystalline  form  and  superior  hardness,  and  its 
falling  to  powder  before  the  blowpipe. 

Obs.  Arragonite  occurs  mostly  in  gypsum  beds  and  de- 
posits of  iron  ore ;  also  in  basalt  and  other  rocks.  The 
coralloidal  forms  are  found  in  iron  ore  beds,  and  are  called 
flos-ferri,  flowers  of  iron.  They  look  like  a  loosely  inter-- 
twined  or  tangled  white  cord. 

'  The  flos-ferri  variety  occurs  at  Lockport  with  gypsum  ; 
also  at  Edenville,  at  the  Parish  iron  ore  bed  in  Rossie,  and 
in  Chester  county,  Pennsylvania.  Arragon  in  Spain  affords- 
six-sided  prisms  of  arragonitej  associated  with  gypsum.  This* 
locality  gave  the  name  to  the  species. 


6,  DOLOMITE — Magnesian  Carbonate  of  Lime. 
Rhombohedral.  R  :  R— 106°  15'.  Cleavage  perfect 
parallel  to  the  primary  faces.  Faces  of  rhom- 
bodedrons  sometimes  curved,  as  in  the  annexed 
figure.  Often  granular  and  massive,  constitu- 
ting extensive  beds. 

Color  white  or  tinged  with  yellow,  red,  green, 

What  are  the  usual  forms  of  arragonite  ?  Does  it  differ  in  composi- 
tion from  calcite?  What  are  its  colors  and  luster?  What  effect  is 
produced  by  the  blowpipe  ? 


DOLOMITE.  119 

brown,  and  sometimes  black.  Luster  vitreous,  a  a  little 
pearly.  Nearly  transparent  to  translucent.  Brittle.  H== 
3-5—4.  Gr=2-8— 2-9. 

Composition.  Dolomite  is  a  compound  of  carbonate  of 
magnesia  and  carbonate  of  lime.  The  common  variety  con- 
sists of  54'2  of  the  latter  to  45*8  of  the  former.  Infusible 
before  the  blowpipe.  Effervesces  with  acids,  but  more 
slowly  than  calc  spar. 

The  principal  varieties  of  this  species  are  as  follows : 

Dolomite. — White  crystalline  granular,  often  not  distin- 
guishable in  external  characters  from  granular  limestone, 
except  that  it  crumbles  more  readily. 

Pearl  spar. — This  variety  occurs  in  pearly  rhombohe- 
drons  with  curved  faces. 

Rhomb  spar,  Brown  spar. — In  rhombohedrons,  which 
become  brown  on  exposure,  owing  to  their  containing  5  to 
10  percent,  ofoxyd  of  iron  or  manganese. 

Micmite. — A  yellowish  brown  fibrous  variety  from  Miemo 
in  Tuscany. 

Gurhofite. — A  compact  white  rock,  looking  like  porcelain 
and  containing  a  few  per  cent,  of  silica. 

Dif.  Distinctive  characters,  nearly  the  same  as  for  cal- 
careous  spar.  It  is  harder  than  that  species,  and  differs  in 
the  angles  of  its  crystals,  and  effervesces  less  freely ;  but 
chemical  analysis  is  often  required  to  distinguish  them. 

Obs.  Massive  dolomite  is  common  in  the  Eastern  States, 
and  constitutes  much  of  the  coarse  white  marble  used  for 
i  building.  Crystallized  specimens  are  obtained  at  the  Quar- 
;  antine,  Richmond  county,  N.  Y.  Rhomb  spar  occurs  in  talc 
at  Smithfield,  R.  I.,  Marlboro,  Vt,  Middlefield,  Mass. ;  pearl 
spar  in  crystals  of  the  above  form  at  Lock  port,  Rochester, 
Glen's  Falls  ;  gurhofite  on  Hustis's  farm,  Phillipstown,  N.  Y. 

Dolomite  was  named  in  honor  of  the  geologist  and  traveler, 
J  Dolomieu. 

Uses.  Dolomite  burns  to  quicklime  like  calc  spai,  and  af- 
fords a  stronger  cement.  The  white  massive  variety  is  used 
extensively  as  marble.  The  magnesian  lime  has  been  sup- 
posed to  injure  soils  ;  but  this  is  believed  not  to  be  the  case 
i  if  it  is  air-slaked  before  being  used.  It  is  also  employed  in 
'the  manufacture  of  Epsom  salts  or  sulphate  of  magnesia. 


What  is  the  composition  of  dolomite  ?    How  does  it  differ  from  cal- 
cite  ?     What  are  its  u^es  ? 


120  SALTS    OP   LIME. 

The  mineral  is  subjected  to  the  action  of  sulpha:  ic  acid  ;  the 
sulphate  of  lime  being  insoluble  is  deposited,  leaving  the  sul- 
phate of  magnesia  in  solution.  A  more  economical  method 
is  to  boil  the  calcined  stone  in  proper  proportions  in  bittern  ; 
the  muriatic  acid  of  the  bittern  takes  up  the  lime. 

Ankerite.  This  species  resembles  brown  spar,  and  like  that  becomes 
brown  on  exposure.  The  primary  is  a  rhombohedron  of  106°  12'.  It 
consists  of  the  carbonates  of  lime,  magnesia,  iron,  and  manganese.  The 
Styrian  iron  ore  beds  and  Saltzburg  are  some  of  its  foreign  localities. 
It  is  said  to  occur  in  veins  at  Quebec  and  at  West  Springfield,  Mass. 

7,     APATITE. — Phosphate  of  Lime. 

In  hexagonal  prisms.  The  annexed  figure  represents  a 
crjstal  from  St.  Lawrence  county,  New  York. 
Cleavage  imperfect. 

Usually  occurs  in  crystals ;  but  occasionally 
massive  ;  sometimes  mammillary  with  a  compact 
fibrous  structure.  Small  crystals  are  occasionally 
transparent  and  colorless,  but  the  usual  color  is 
green,  often  yellowish-green,  bluish-green,  and  grayish-green ; 
sometimes  yellow,  blue,  reddish  or  brownish.  Coarse  crys- 
tals nearly  opaque.  Luster  resinous,  or  a  little  oily.  H=5. 
Gr=3 — 3 '25.  Brittle.  Some  varieties  phosphoresce  when 
heated,  and  some  become  electric  by  friction. 

Composition:  phosphate  of  lime  92*1,  fluorid  of  calcium 
7'0,  chlorid  of  calcium  0*9.  Infusible  before  the  blowpipe 
except  on  the  edges.  Dissolves  slowly  in  nitric  acid  without 
effervescence.  Its  constituents  are  contained  in  the  bones 
and  ligaments  of  animals,  and  the  mineral  has  probably  been 
derived  in  many  cases  from  animal  fossils.* 

Asparagus  stone  is  a  translucent  wine-yellow*  variety  oc- 
curring in  talc  at  Zillerthal  in  the  Tyrol.  Phosphorite  is  a 
massive  variety  from  Estremadura  in  Spain,  and  Schlacken- 
wald  in  Bohemia.  Moroxite  is  a  greenish-blue  variety  from 
Arendal.  Eupyrchroite  (Emmons)  is  a  fibrous  mammillary 
variety  from  Crown  Point,  Essex  county,  N.  Y. 

What  is  the  common  form  of  apatite  ?  is  colcrs  and  appearance?'  Is 
it  harder  than  calc  spar  1  What  is  the  principal  constituent  in  its  com- 
position 1  What  is  a  probable  origin  of  this  mineral  in  many  cases  1 

*  Bones  contain  55  per  cent,  of  phosphate  of  lime,  with  some  fluorid 
of  calcium,  3  to  12  per  cent,  of  carbonate  of  lime,  some  phosphate  of 
magnesia  and  chlorid  of  sodium,  besides  33  per  cent,  of  animal  matter. 


FLUOR    SPAR. 


121 


Dif.  Distinguished  by  its  inferior  hardness  front  beryl,  it 
being  easily  scratched  with  a  knife  ;  by  dissolving  in  acids 
without  effervescence  from  carbonate  of  lime  and  other  car- 
bonates  ;  by  its  difficult  fusibility,  and  giving  no  metallic 
reaction  before  the  blowpipe  from  phosphate  of  lead  and 
other  metallic  species.  Its  phosphorescence  is  also  an  im- 
portant characteristic. 

Obs.  Apatite  occurs  in  gneiss  and  mica  slate,  granular 
limestone,  and  occasionally  in  ancient  volcanic  rocks.  The 
finest  localities  in  the  United  States  occur  in  granular  lime- 
stone. The  crystals  from  the  limestone  of  St.  Lawrence 
county,  N.  Y.,  are  among  the  largest  yet  discovered  in  any 
part  of  the  world.  One  from  Robinson's  farm  measured  a 
foot  in  length  and  weighed  18  pounds.  But  they  are  nearly 
opaque  and  the  edges  are  usually  rounded.  They  occur  with 
scapolite,  sphene,  &c.  Edenville  and  Amity,  Orange  county, 
N.  Y.,  afford  fine  crystals  from  half  an  inch  to  twelve  inches 
long.  At  Westmoreland,  N.  H.,  fine  crystals  are  obtained  in 
a  vein  of  feldspar  and  quartz  ;  also  at  Blue  Hill  bay  in  Maine. 
Bolton,  Chesterfield,  Chester,  Mass.,  are  other  localities.  A 
beautiful  blue  variety  is  obtained  at  Dixon's  quarry,  Wil- 
mington, Delaware. 

The  name  apatite,  from  the  Greek  apatao,  to  deceive,  was 
given  in  allusion  to  the  mistake  of  early  mineralogists  re- 
specting the  nature  of  some  of  its  varieties. 

8.     FLUOR  SPAR — Fhtorid  of  Calcium,  Fluate  of  Lime. 

Monometric.  Cleavage  octahedral,  perfect.  Secondary 
forms,  the  following : 


Rarely  occurs  fibrous  ;  often  compact,  coarse  or  fine  gran- 
ular.    Colors  usually  bright  ;  white,  or  some  shade  of  light 
green,  purple,  or  clear  yellow  are  most   common;  rarely 
-red   and   sky-blue  ;    colors  of  massive  varieties  often 


rose- 


How  is  apatite  distinguished  from  beryl?  how  from  carbonates?  how 
from  phosphate  of  lead  ?     What  is  said  of  the  crystalline  form  and 
cleavage  of  fluor  spar  ?     What  is  said  of  its  colors  and  appearance  ? 
11 


122  SALTS    OF   LIME. 

banded.  The  crystals  are  transparent  or  translucent.  H=4. 
Gr=3-14— 3-18.  Brittle. 

Composition :  fluorine  47*7,  calcium  52*3.  Phosphoresces 
on  a  hot  iron,  giving  out  a  bright  light  of  different  colors ; 
in  some  varieties  the  light  is  emerald  green ;  in  others,  pur- 
ple, blue,  rose-red,  pink,  or  an  orange  shade.  Before  the 
blowpipe  it  decrepitates,  and  ultimately  fuses  to  an  enamel. 
Pulverised  and  moistened  with  sulphuric  acid,  a  gas  is  given 
off  which  corrodes  glass. 

The  name  chlorophane  has  been  given  to  the  variety  that 
affords  a  green  phosphorescence. 

Dif.  In  its  bright  colors,  fluor  resembles  some  of  the 
gems,  but  its  softness  at  once  distinguishes  it.  Its  strong 
phosphorescence  is  a  striking  characteristic  ;  and  also  its 
affording  easily,  with  sulphuric  acid  and  heat,  a  gas  that  cor- 
rodes glass. 

Obs.  Fluor  spar  occurs  in  veins  in  gneiss,  mica  slate, 
clay  slate,  limestone,  and  sparingly  in  beds  of  coal.  It  is  the 
gangue  in  some  lead  mines. 

Cubic  crystals  of  a  greenish  color,  over  a  foot  each  way, 
hav^  been  obtained  at  Muscolorige  Lake,  St.  Lawrence 
county,  N.  Y.  Near  Shawneetown  on  the  Ohio,  a  beautiful 
purple  fluor  in  grouped  cubes  of  large  size  is  obtained  from 
limestone  and  the  soil  of  the  region.  At  Westmoreland, 
N.  IL,  at  the  Notch  in  the  White  Mountains,  Blue  Hill  Bay, 
Maine,  Putney,  Vt.,  and  Lockport,  N.  Y.,  are  other  locali- 
ties. The  chlorophane  variety  is  found  with  topaz  at  Hun- 
tington,  Conn. 

In  Derbyshire,  England,  fluor  spar  is  abundant,  and  hence 
it  has  received  the  name  of  Derbyshire  spar.  It  is  a  common 
mineral  in  the  mining  districts  of  Saxony. 

Fluorid  of  calcium  is  also  found  in  the  enamel  of  teeth, 
in  bones  and  some  other  parts  of  animals  ;  also  in  certain 
parts  of  many  plants  ;  and  by  vegetable  or  animal  decompo- 
sition it  is  afforded  to  the  soil,  to  rocks,  and  also  to  coal  beds 
in  which  it  has  been  detected. 

Uses.  Massive  fluor  receives  a  high  polish  and  is  worked 
into  vases,  candlesticks  and  various  ornaments,  in  Derbyshire, 
England.  Some  of  the  varieties  from  this  locality,  consisting 
of  rich  purple  shades  banded  with  yellowish  white,  are  very 

What  is  said  of  the  phosphorescence  of  calc  spar?  Of  what  does  it 
consist?  What  is  chlorophane  ?  How  is  fluor  spar  distinguished  from 
the  gems?  What  arc  its  uses  ? 


FLUOR    SPAR.  123 

beautiful.  The  mineral  is  difficult  to  work  on  account  of  be- 
ing brittle.  It  is  usually  turned  in  a  lathe,  and  worked  down 
first  with  a  fine  steel  tool ;  then  with  a  coarse  stone,  and 
afterwards  with  pumice  and  emery.  The  crevices  which 
occur  in  the  masses  are  sometimes  concealed  by  filling  them 
with  galena,  a  mineral  often  found  with  the  fluor.  Fluor 
spar  is  also  used  for  obtaining  fluoric  acid,  which  is  employed 
in  etching.  To  etch  glass,  a  picture,  or  whatever  design  it 
is  desired  to  etch,  is  traced  in  the  thin  coating  of  wax*  with 
which  the  glass  is  first  covered  ;  a  very  small  quantity  of  the 
liquid  fluoric  acid  is  then  washed  over  it ;  on  removing  the 
wax,  in  a  few  minutes,  the  picture  is  found  to  be  engraved  on 
the  glass.  The  same  process  is  used  for  etching  seals,  and 
any  siliceous  stone  will  be  attacked  with  equal  facility.  Fluor 
spar  is  also  used  as  a  flux  to  aid  in  reducing  copper  and 
other  ores,  and  hence  the  name  fuor. 

Hayesine  or  Hydrous  Borate  of  Lime.  Occurs  in  snowy  white  inter- 
woven fibers,  with  gypsum  and  alum  on  the  plains  of  Iquique,  S.  A. 

Hydroboracite.  A  hydrous  borate  of  lime  and  magnesia  resembling 
somewhat  a  white  fibrous  gypsum.  It  is  of  Caucasian  origin. 

Oxalate  of  Lime.  Observed  on  calc  spar  in  small  oblique  crystals. 
Locality  unknown. 

Nitrate  of  Lime.  In  white  delicate  efflorescences  ;  deliquescent. 
Also  in  solution  in  some  waters.  The  salt  is  formed  in  calcareous 
caverns  and  covered  spots  of  earth  where  the  soil  is  calcareous.  It  ia 
extensively  used  in  the  manufacture  of  saltpeter,  (nitrate  of  potash.) 
Occurs  in  the  caverns  of  Kentucky  and  other  Western  States. 

7.     MAGNESIA. 

The  sulphates  and  nitrate  of  magnesia  are  soluble,  and  are 
distinguished  by  their  bitter  taste.  The  other  native  mag- 
nesian  salts  are  insoluble.  The  presence  of  magnesia  when 
no  metallic  oxyds  are  present  is  indicated  by  a  blowpipe 
experiment :  after  heating  a  fragment,  moisten  it  with  a  solu- 
tion of  nitrate  of  cobalt,  and  then  subject  it  again  to  the  heat 

How  is  glass  etched  by  means  of  fluor  spar  1  What  is  the  origin  of 
the  name  fluor  1  What  is  said  of  the  occurrence  and  uses  of  nitrate 
of  lime  ?  What  is  the  taste  of  soluble  salts  of  magnesia  ?  What  blow- 
pipe test  distinguishes  them  1 

*  The  best  material  is  a  mixture  of  bees  wax  and  turpentine  resin 
melted  together. 


124  SALTS    OF   MAGNESIA. 

of  the  blowpipe,  and  it  will  become  pale-red,  and  deepen  in 
color  by  fusion. 

Specific  gravity  of  the  species  in  this  family,  below  3. 
Hardness  of  some  species  as  high  as  7. 

EPSOM  SALT. — Sulphate  of  Magnesia. 

Trimetric.  In  modified  rhombic  prisms,  (fig.  8,  page  26.) 
M  :  M  =90°  38'.  Cleavage  perfect  parallel  with  the  shorter 
diagonal.  Usually  in  fibrous  crusts,  or  botryoidal  masses, 
of  a  white  color.  Luster  vitreous — earthy.  Very  soluble, 
and  taste  bitter  and  saline. 

Composition  :  magnesia  16*7,  sulphuric  acid  32'4,  water 
50'9.  Deliquesces  before  the  blowpipe.  Does  not  effer- 
vesce with  acids. 

Dif.  The  fine  spicula-like  crystalline  grains  of  Epsom 
salt,  as  it  appears  in  the  shops,  distinguish  it  from  Glauber 
salt,  which  occurs  usually  in  thick  crystals. 

Obs.  The  floors  of  the  limestone  caves  of  the  West  often 
contain  Epsom  salt  in  minute  crystals  mingled  with  the 
earth.  In  the  Mammoth  Cave,  Ky.,it  adheres  to  the  roof  in 
loose  masses  like  snow-balls.  It  occurs  as  an  efflorescence 
on  the  east  face  of  the  Helderberg,  10  miles  from  Coeymans. 
The  fine  efflorescences  suggested  the  old  name  hair  salt. 

At  Epsom  in  Surrey,  England,  it  occurs  dissolved  in  min- 
eral springs,  and  from  this  place  the  salt  derived  the  name 
it  bears.  It  occurs  at  Sedlitz,  Arragon,  and  other  places  in 
Europe  ;  also  in  the  Cordilleras  of  Chili ;  and  in  a  grotto  in 
Southern  Africa,  where  it  forms  a  layer  an  inch  and  a  half 
thick. 

Uses.  Its  medical  uses  are  well  known.  It  is  obtained 
for  the  arts  from  the  bittern  of  sea-salt  works,  and  quite 
largely  from  magnesian  carbonate  of  lime,  by  decomposing 
it  with  sulphuric  acid.  The  sulphuric  acid  takes  the  lime 
and  magnesia,  expelling  the  carbonic  acid  ;  and  the  sulphate 
of  magnesia  remaining  in  solution  is  poured  off  from  the  sul- 
phate of  lime,  which  is  insoluble.  It  is  then  crystallized  by 
evaporation. 

MAGXESITE. — Carbonate  of  Magnesia. 

Rhombohedral ;  R:R  =  107°22.  Cleavage  rhombohe- 
dral,  perfect.  Often  in  fibrous  plates  the  surface  of  which 


Of  what  does  Epsom  salt  consist?     Where  does  it  occur?     Whence 
the  name  Epsom  ? 


CARBONATE    OF    MAGNESIA.  125 

frequently  consists  of  minute  acicular  crystals  ;  also  granular 
and  compact  and  in  tuberous  forms.  Color  white,  yellow- 
ish  or  grayish-white  or  brown.  Luster  vitreous ;  fibrou3 
varieties  often  silky.  Transparent  to  opaque.  H  =  3 — 4. 
Gr  =  2.8— 3. 

Composition:  carbonic  acid  51*7,  and  magnesia  48*3. 
Infusible  before  the  blowpipe.  Dissolves  slowly  with  little 
effervescence  in  nitric  or  sulphuric  acid. 

Dif.  Resembles  some  varieties  of  carbonate  of  lime  and 
dolomite  ;  but  effervesces  more  feebly  in  acids,  does  not  burn 
to  quicklime,  and  the  light  before  the  blowpipe  is  less  intense. 
The  fibrous  variety  is  distinguished  from  amianthus  and  other 
fibrous  minerals  associated  with  it,  by  its  greater  hardness 
and  more  vitreous  luster,  and  from  siliceous  minerals  gen- 
erally by  its  complete  solubility  in  acids. 

Obs.  Magnetite  is  usually  associated  with  magnesian 
rocks,  especially  serpentine.  At  Hoboken,  N.  J.,  it  occurs 
in  this  rock  in  fibrous  seams  ;  similarly  at  Lynnfield,  Mass. ; 
and  at  Bolton,  imperfectly  fibrous,  traversing  white  lime- 
stone. 

Uses.  When  abundant  it  is  a  convenient  material  for  the 
manufacture  of  sulphate  of  magnesia  or  Epsom  salt,  to  make 
which,  requires  simply  treatment  with  sulphuric  acid. 

BRUCITE. — Hydrate  of  Magnesia. 

In  foliated  hexagonal  prisms  and  plates.  Structure  thii. 
foliated,  and  thin  laminae  easily  separated  and  translucent  • 
flexible  but  not  ela  tic.  Color  white  and  pearly,  often  gray- 
ish or  greenish.  H  =  1-5.  Gr  =  2'35. 

Composition:  magnesh  69-7,  water  3O3.  Infusible  be- 
fore the  blowpipe,  but  becomes  opaque  and  friable.  Entirely 
soluble  in  the  acids  without  effervescence. 

Dif.  It  resemb'es  talc  and  gypsum,  but  is  soluble  in  acids  ; 
it  differs  from  heulandite  and  st'lbite,  also  by  its  infusibility. 

Obs.  Occurs  in  serpenti.ie  at  Hoboken,  N.  J.,  and  Rich- 
mond Co.,  N.  Y.,  also  at  Sw'naness  in  Unst,  one  of  the 
Shetland  Isles. 

Nemalite  is  a  fibrous  hydrate  of  magnesia  or  brucite.  The 
following  are  its  charicters  ; 

Of  what  does  magnesite  consist?     How  is  it  distinguished  from  most 
earthy  minerals  ?     How  from   calc   spar  1     For  what  use  is  it  fitted  ? 
What  is  the  appearance  of  nemalite  ?  its  composition  ?  its  locality  ? 
11* 


128  SALTS    OF    MAGNESIA. 

Neatly  fibrous  and  silky ;  fibres  brittle  and  easily  sepera- 
ble.  Color  whitish,  grayish  or  bluish  white  ;  transparent, 
but  becomes  opaque  and  crumbling  on  exposure.  H  =  2. 
Gr  =  2-35— 2-4. 

Composition :  magnesia  62'0  ;  protoxyd  of  iron  4-6  ;  water 
28'4  ;  carbonic  acid  4'1  ; — (Whitney.)  In  the  flame  of  a 
candle  the  fibres  become  opaque,  brownish  and  rigid,  and  in 
this  state  easily  crumble  in  the  fingers.  Phosphoresces  with 
a  yellow  light  when  rubbed  wish  a  piece  of  iron. 

Dif.  Resembles  abestus  or  amianthus,  but  differs  in 
becoming  brittle  before  the  blowpipe. 

Obs.  Occurs  in  serpentine  at  Hoboken,  N.  J.,  in  green- 
stone at  Piermont,  Rockland  Co.,  N.  Y.,  and  Bergen  Hill, 
N.  J. 

Hydromagnesite.  This  name  is  given  to  an  earthy  white  pul- 
verulent hydrous  carbonate  of  magnesia,  from  Hoboken,  N.  J. 

BORACITE. — Borate  of  Magnesia. 

Monometric.  Cleavage  octahedral ;  but  only  in  traces. 
Usual  in  cubes  with  only  the 
alternate  angles  replaced  ;  or 
having  all  replaced,  but  four 
of  them  different  from  the  oth- 
er four.  The  crystals  are 
translucent  and  seldom  more  than  a  quarter  of  an  inch 
through.  Color  white  or  grayish  ;  sometimes  yellowish  or 
greenish.  Luster  vitreous.  H=7.  Gr=2'97.  Becomes 
electric  when  heated,  the  opposite  angles  of  the  cube  be- 
coming of  opposite  poles,  one  north  and  the  other  south. 

Composition  :  boracic  acid  62*8,  magnesia  37'2.  Intu- 
mesces  before  the  blowpipe  and  forms  a  glassy  globule, 
which  becomes  crystalline  and  opaque  on  cooling. 

Dif.  Distinguished  readily  by  its  form,  high  hardness, 
and  pyro-electric  properties. 

Obs.  Boracite  is  found  only  with  gypsum  and  common 
salt.  It  occurs  near  Luneberg  in  Lower  Saxony,  and  near 
Kiel  in  the  adjoining  dutchy  of  Holstein. 

Nitrate  of  Magnesia.  Occurs  in  white  deliquescent  efflorescences, 
having  a  bitter  taste,  associated  with  nitrate  of  lime,  in  limestone  cav- 

What  is  Brucite?    What  is  its  appearance  ?     How  is  it  distinguished 
from  talc,  gypsum,  and  other  minerals  ?     What  is  said  of  the  crystals  of 
boracite  ?     What  is  stated  of  its  electric  properties?     What  is  its  coir 
position  1     What  is  its  mode  of  occurrence  1 


SALTS    OF    ALUMINA.  127 

erns.  It  is  used,  like  its  associate,  in  the  manufacture  of  saltpeter 
(see  page  102.) 

Polyhalite.  A  brick-red  saline  mineral,  with  a  weak  bitter  taste, 
occurring  in  masses  which  have  a  somewhat  fibrous  appearance.  Con- 
sists of  the  sulphates  of  lime,  potash  and  magnesia,  with  six  per  cent, 
of  water. 

Wagnerite.  A  fluo-phosphate  of  magnesia,  occurring  in  yellowish 
or  grayish  oblique  rhombic  prisms.  Insoluble.  H=5 — 5'5.  Gr=3  1. 
From  Saltzberg,  Germany. 

Ehodizite.  Resembles  boracite  in  its  crystals,  but  tinges  the  blow- 
pipe flame  deep  red.  Occurs  with  the  red  tourmaline  of  Siberia. 

8.     ALUMINA. 

The  compounds  of  alumina  may  often  be  distinguished  by 
a  blowpipe  experiment.  If  a  fragment  of  alumina  after 
having  been  heated  to  redness  be  moistened  with  a  solution 
of  nitrate  of  cobalt  and  again  heated,  it  assumes  before  fu- 
sion a  blue  color.  This  is  a  good  test,  and  distinguishes 
aluminous  from  magnesian  minerals,  except  when  the  oxyds 
of  the  metals  are  present. 

The  sulphates,  fluorids  and  some  of  the  phosphates,  (tho 
salts  included  in  this  family,)  are  soluble  with  more  or  less 
difficulty,  in  the  acids ;  and  some  of  the  sulphates  (tho  vari- 
ous alums)  dissolve  readily  in  water. 

The  solution  in  acids  takes  place  without  effervescence, 
and  without  forming  a  jelly  like  many  silicates  of  alumina 
(the  zeolites,  &c.) 

Specific  gravities  of  the  species  below  3*1.  Hardness  of 
some  species  as  high  as  6. 

NATIVE    ALUM. 

^,  •;>.'---.   ~       * 

Monometric.     Cleavage  octahedral.     Occurs  in  octahe- 
drons ;  but  usually  in  silky  fibrous  masses,  or  in 
efflorescent  crusts.     Taste  sweetish  astringent. 
There  are  several  kinds  of  native  alum,  dif- 
fering in  one  of  the  ingredients  in  their  consti- 
,  tution,  but  resembling  one  another  in  crystalli- 
,  zing  in  octahedrons,  and  in  containing  the  in- 
gredients in  exactly  the  same  proportions.     They  all  contain 

What  blowpipe  experiment  distinguishes  alumina  ?  What  is  said  of 
the  sulphates  of  alumina  1  What  is  the  composition  of  the  alums  ? 


128  SALTS    OF   ALUMINA. 

24  parts  of  water  to  1  part  of  sulphate  of  alumina,  and  1  part 
of  some  other  sulphate.  In  potash-alum,  this  sulphate  is  a 
sulphate  of  potash.  This  is  the  common  alum  of  the  shops. 

The  corresponding  sulphate  in  the  other  alums  is  as  fol- 
lows : — 

Soda-alum,  sulphate  of  soda  ; 

Magnesia-alum,  sulphate  of  magnesia  ; 

Ammonia-alum,  sulphate  of  ammonia  ; 

Iron-alum,  sulphate  of  iron  ; 

Manganese-alum,  sulphate  of  manganese. 

Besides  these  there  is  also  a  hydrous  sulphate  of  alumina 
without  any  other  sulphate  ;  it  is  called  feather-alum,  and  is 
even  of  more  common  occurrence  than  any  of  the  true 
alums. 

These  alums  are  formed  from  the  decomposition  of  pyrites, 
in  contact  with  clay.  Iron  pyrites  is  a  compound  of  sulphur 
and  iron ;  in  decomposition,  its  sulphur  and  iron  unite  with 
oxygen  derived  from  the  moisture  present,  and  it  then  be- 
comes sulphate  of  iron,  or  a  compound  of  sulphuric  acid  and 
oxyd  of  iron.  This  sulphuric  acid,  or  part  of  it,  by  uniting 
with  the  alumina  of  the  clay  rock,  produces  a  sulphate  of 
alumina.  To  form  a  true  alum,  a  little  potash,  or  soda,  &c. 
must  be  present  in  the  clay.  The  iron  of  the  iron  alum  pro- 
ceeds from  the  pyrites  which  undergoes  the  decomposition. 

These  compounds  differ  but  little  in  taste  and  appear- 
ance. 

Obs.  Potash  alum  and  more  abundantly  the  sulphate  of 
alumina  (or  feather  alum),  and  sulphate  of  alumina  and  iron, 
impregnate  frequently  clay-slates,  which  are  then  called 
aluminous  slates  or  shales.  These  alum  rocks  are  often 
quarried  and  lixiviated  for  the  alum  they  contain.  The  rock 
is  first  slowly  heated  after  piling  it  in  heaps,  in  order  to  de- 
compose the  remaining  pyrites  and  transfer  the  sulphuric 
acid  of  any  sulphate  of  iron  to  the  alumina  and  thus  produce 
the  largest  amount  possible  of  sulphate  of  alumina.  It  is 
next  lixiviated  in  stone  cisterns.  The  lye  containing  this  sul- 
phate is  afterwards  concentrated  by  evaporation,  and  then 
the  requisite  proportion  of  potash  (sulphate  or  muriate,  alum 
containing  potash  as  well  as  alumina)  is  added  to  the  lix- 


What  is  the  composition  of  common  potash  alum  ?  What  of  a  soda 
alum  1  What  are  alum  shales'?  Whence  the  alum  or  sulphate  of  alum- 
ina they  contain  1  How  is  alum  obtain  from  alum  shale  ? 


ALUM    STONE  129 

ivium.  A  precipitate  of  alum  falls  which  is  afterwards  wash- 
ed and  re-crystallized.  The  mother  liquor  left  after  the  pre- 
cipitation is  also  treated  for  more  alum.  This  process  is 
carried  on  extensively  in  Germany,  France,  at  Whitby  in 
Yorkshire,  Hurlett  and  Campsie,  near  Glasgow,  in  Scot- 
land. Cape  Sable  in  Maryland,  affords  large  quantities  of 
alum  annually.  The  slates  of  coal  beds  are  often  used  to 
advantage  in  this  manufacture,  owing  to  the  decomposing 
pyrites  present.  At  Whitby,  130  tons  of  calcined  schist 
give  one  ton  of  alum.  In  France,  ammoniacal  salts  are 
used  instead  of  potash,  and  an  ammoniacal  alum  is  formed. 

Soda  alum  has  been  observed  at  the  Solfataras  in  Italy, 
near  Mendoza  in  South  America,  on  the  island  of  Milo  in 
the  Grecian  Archipelago.  Magnesia  alum  forms  large  fib- 
rous masses,  delicately  silky,  near  Iquique,  S.  A.  This  is 
the  Pickeringite  of  Mr.  A.  A.  Hayes.  Ammonia  alum  oc- 
curs at  Tschermig  in  Bohemia. 

ALUM    STONE. 

Rhombohedral,  with  a  perfect  cleavage  parallel  with  a, 
(fig.  62,  p.  39.)  R  :  R=92°  50'.  Also  massive.  Color 
white,  grayish  or  reddish.  Luster  of  crystals  vitreous,  or  a 
ittle  pearly  on  a.  Transparent  to  translucent.  H=5.  Gr= 
2-58— 2-75. 

Composition :  sulphuric  acid  25*0,  alumina  43*9,  silica 
34*0,  potash  3*1,  water  and  loss  4*00=100.  Decrepitates 
n  the  blowpipe  flame  and  is  infusible  both  alone  and  with 
soda.  In  powder,  soluble  in  sulphuric  acid. 

Dif.  Distinguished  by  its  infusibility,  in  connection  with 
ts  complete  solubility  in  sulphuric  acid  without  forming  a 
jelly. 

Obs.  Found  in  rocks  of  volcanic  origin  at  Tolfa,  near 
Rome,  and  also  at  Beregh  and  elsewhere  in  Hungary. 

Uses.  At  Tolfa,  alum  is  obtained  from  it  by  repeatedly 
roasting  and  lixiviating  it  and  finally  crystallizing  by  evapo- 
ration. The  variety  found  in  Hungary  is  so  hard  as  to  ad- 
mit of  being  used  for  millstones. 

Websterite.  Another  sulphate  of  alumina,  in  compact  reniform 
masses  and  tasteless.  From  Newhaven  in  Sussex,  Epernay  in  France, 
and  Halle  in  Prussia.  It  is  called  also  aluminite. 


What  is  the  color  and  appearance  of  alum  stone?     What  its  compo- 
eition  ]     What  its  use,  and  where  is  it  extensively  employed  ? 


130  SALTS    OF    ALUMINA. 

WAVELLITE. 

Trimetric.  Usually  in  small  hemispheres  a  third  or  half 
an  inch  across,  attached  to  tho 
surface  of  rocks,  and  having  a 
finely  radiated  structure  within  ; 
when  broken  off  they  leave  a 
stellate  circle  on  the  rock. 
Sometimes  in  rhombic  crystals. 

Color  white  or  yellowish  arid  brownish,  with  a  somewhat 
pearly  or  resinous  luster.  Sometimes -green,  gray  or  black, 
Translucent.  H=3'5— 4.  Gr=2-23— 2-37. 

Composition:  alumina  37'2,  phosphoric  acid  35*1,  watei 
28-0.  Whitens  before  the  blowpipe  but  does  not  fuse.  In 
powder,  dissolves  in  heated  nitric  or  sulphuric  acid. 

Dif.  Distinguished  from  the  zeolites,  some  of  which  it 
resembles,  by  giving  the  reaction  of  phosphorus  and  also  by 
dissolving  in  acids  without  gelatinizing.  Cacoxene,  to  which 
it  is  allied,  becomes  dark  reddish-brown  before  the  blowpipe, 
and  gives  the  reaction  of  iron. 

Obs.  Near  Saxton's  River,  Bellows  Falls,  is  the  only 
locality  known  in  the  United  States.  It  was  first  discover- 
ed  by  Dr.  Wavel,  in  clay  slate  in  Devonshire.  Occurs  also 
in  Bohemia  and  Bavaria. 

Fischerite  is  another  hydrous  phosphate  of  alumina  containing  less 
phosphoric  acid.  Gr=2'46.  Color  dull  green.  Translucent.  Some- 
times in  six-sided  prisms.  From  the  Ural. 

TURQUOIS. 

In  opaque  reniform  masses  without  cleavage,  of  a  bluish 
green  color  and  somewhat  waxy  luster.  H=6.  Gr= 
2-8—3. 

Composition:  phosphoric  acid  30*9,  alumina  44'5,  oxyd  of 
copper  3-7,  protoxyd  of  iron  1-8,  water  19-0=99-9. 
Before  the  blowpipe  it  is  infusible,  but  colors  the  flame  green 
and  in  the  inner  cone  becomes  brown.  Loses  its  blue  color 
in  muriatic  acid. 

Dif.  Distinguished  from  bluish  green  feldspar,  which  it 
resemble?,  by  its  infusibility  and  the  reaction  of  phosphorus. 

Obs.     Turquois  is  brought  from  a  mountainous  district  in 

What  is  the  usual  appearance  of  Wayellite?  What  is  its  composi- 
tion ]  What  distinguishes  it  from  the  zeolites  ?  What  is  the  color  and 
appearance  of  turquois  ?  Its  constituents  ?  Huw  is  it  distinguished 
from  a  variety  of  feldspar  1  Where  is  it  found  { 


OIBBSITE.  131 

Persia,  not  far  from  Nichabour,  and  according  to  Agaphi 
occurs  in  veins,  that  traverse  the  mountain  in  every  direc- 
tion. 

The  callais  of  Pliny  was  probably  turquois.  Pliny,  in 
his  description  of  it,  mentions  the  fable  that  it  was  found  in 
Asia,  projecting  from  the  surface  of  inaccessible  rocks, 
whence  it  was  obtained  by  means  of  slings. 

Uses.  Turquois  receives  a  fine  polish  and  is  highly  os- 
teemed  as  a  gem.  In  Persia  it  is  much  admired,  and  the 
Persian  king  is  said  to  retain  for  himself,  all  the  large  and 
more  finely  tinted  specimens.  The  occidental  or  bone  Tur- 
quois, a  much  inferior  and  softer  stone,  is  said  to  be  phos- 
phate of  lime,  colored  with  oxyd  of  copper.  Green  mala' 
chite  is  sometimes  substituted  for  turquois,  but  it  is  much  soft- 
er and  has  a  different  tint  of  color.  The  stone  is  so  well 
imitated  by  art  as  scarcely  to  be  detected  except  by  chemi- 
cal tests.  The  imitation  is  much  softer  than  true  turquois. 

GIBBSITE. — Hydrate  of  Alumina. 

In  small  stalactitic  shapes  or  mammillary  and  incrusting. 
Color  grayish  or  greenish  white  ;  surface  smooth  but  nearly 
dull.  Structure  sornetim'es  nearly  fibrous.  H=3 — 3*5. 
Gr=2-3— 2-4. 

Composition :  alumina  64'8,  water  35'7. — (Torrey.)  Re- 
cent examinations  have  detected  a  large  por-centage  of  phos- 
phoric acid  in  some  specimens ;  but  Prof.  B.  Silliman,  Jr.  has 
also  found,  in  specimens  examined  by  him,  as  impurity  a 
proportion  of  silica  without  phosphoric  acid.  The  mineral 
has  resulted  from  the  decomposition  of  feldspar  or  some 
aluminous  mineral,  and  probably  varies  in  composition.  It 
whitens  but  does  not  fuse  before  the  blowpipe. 

Dif.     Resembles  chalcedony  but  is  softer. 

Obs.  Occurs  in  a  bed  of  brown  iron  ore  at  Richmond, 
Mass.,  and  at  Unionvale,  Dutchess  county,  N.  Y.  This 
species  was  named  in  honor  of  Col.  George  Gibbs. 

Lazulite.  In  compact  masses  ;  rarely  in  prismatic  crystals.  Color 
fine  azure  blue,  and  nearly  opaque,  'with  a  vitreous  luster.  H=5 — 6. 
Gr=3'057.  Brittle.  Contains  phosphoric  acid  41-8,  alumina  35'7, 
magnesia  9'3,  silica  21,  protoxyd  of  iron  2'6,  water  6'1=97'7.  It  in- 

What  is  said  of  its  use?  How  is  it  distinguished  from  false  or  arti- 
ficial turquois  ?  What  is  the  appearance  of  Gibbsite  ?  What  is  said 
of  its  composition  ?  How  is  it  distinguished  from  chalcedony  1  Wha 
is  the  constitution  of  lazulite?  its  color  ? 


132 


SILICA. 


tumesces  before  the  blowpipe  without  fusing.  Occurs  in  veins  in  clay 
slate  at  Saltzberg  and  in  Styria ;  in  the  United  States,  near  Crowder 
Mountain,  Lincoln  county,  N.  C. 

Mellite  or  Honey  stone.  In  square  octahedrons,  looking  like  a  honey- 
yellow  resin  ;  may  be  cut  with  a  knife.  It  is  mellate  of  alumine. 
Found  in  Prussia  and  Austria. 

Cryolite.  In  snow  white  masses,  having  rectangular  cleavages,  and 
remarkable  for  melting  easily  in  the  flame  of  a  candle,  to  which  its 
name  (from  the  Greek  kruos,  ice,)  alludes.  H=2  25 — 25.  Gr=2'95. 
It  is  a  fluorid  of  aluminium  and  sodium.  From  Greenland. 

Chiolite  is  near  cryolite  in  composition  and  characters.  H=3-5. 
Gr=2-6— 2-77.  From  Siberia. 

Fluellite.  From  Cornwall,  in  minute  white  rhombic  octahedrons. 
Contains  fluorine  and  aluminium. 

Childrenite.  Found  in  Derbyshire,  Eng.,  in  minute  yellowish  brown 
crystals  coating  spathic  iron.  Supposed  to  consist  of  phosphoric  acid, 
alumina  and  iron. 

Amblygonite.  A  compound  of  phosphoric  acid,  alumina  and  lithia. 
Found  in  Saxony,  in  pale  green  crystals. 

Diaspore,  or  Dihydratc  of  Alumina.  Occurs  in  irregular  lamellar 
prisms,  having  a  brilliant  cleavage  ;  color  greenish  gray  or  hair  brown. 
H— 6 — 6*5.  Gr==3'43.  It  decrepitates  with  violence  before  the  blow- 
pipe. From  the  Urals,  in  granular  limestone. 

CLASS  VI.— EARTHY  MINERALS. 

1.     SILICA. 

QUARTZ. 

Rhombohedral.  Occurs  usually  in  six-sided  prisms,  more 
or  less  modified,  terminated  with  six-sided  pyramids  :  R ;  R= 
94°  15'.  No  cleavage  apparent,  seldom  even  in  traces  ;  but 
sometimes  obtained  by  heating  the  crystal  and  plunging  it 
into  cold  water.  The  following  are  some  of  its  forms  : 
1  2  3  4  5 


Occurs  sometimes  in  coarse  radiated  forms  ;  also  coarse 
and  fine  granular ;  also  compact,  either  amorphous  or  pre- 
senting stalactitic  and  mamillary  shapes. 

Crystals  are  often  as  pellucid  as  glass,  and  usually  color- 

What  is  the  usual  form  of  quartz  crystals  ? 


QtTARTZ.  133 

less ;  but  sometimes  present  topaz-yellow,  amethystine,  rose 
or  smoky  tints.  Also  of  all  degrees  of  transparency  to 
opacity,  and  of  various  shades  of  yellow,  red,  green,  blue  and 
brown  colors,  to  black.  In  some  varieties  the  colors  are  in 
bands,  stripes,  or  clouds.  H=7.  Gr=2'6 — 2'7. 

Composition  :  quartz  is  pure  silica.  Opaque  varieties  of- 
ten contain  oxyd  of  iron,  clay,  chlorite  or  some  other  mineral 
disseminated  through  them.  Alone  before  the  blowpipe  infu- 
sible, but  with  soda  melts  readily  with  a  brisk  effervescence. 

Dif.  Quartz  is  a  constituent  of  many  rocks,  and  composes 
most  of  the  pebbles  of  the  soil  or  gravel  beds.  There  is  no 
mineral  which  takes  on  so  many  forms  and  colors,  yet 
none  is  more  easily  distinguished.  A  few  simple  trials 
are  all  that  is  required. 

1.  Hardness — scratches  glass  with  facihty. 

2.  Inf  usability — not  melting  in  any  heat  obtained  with  the 
blowpipe. 

3.  Insolubility — not  being  attacked,  like  limestone,  in  any 
way,  by  the  three  acids. 

4.  Absence  of  any  thing  like  cleavage.     One  variety  ap- 
pears to  be  laminated,  but  it  consists  merely  of  apposed 
plates,  which  are  the   result  of  having  been  formed  or  de- 
posited in  successive  layers,   and  cannot  be  mistaken  for 
cleavage  plates- 

To  these  characteristics,  its  action  with  soda  might  be 
added.  In  the  crystallized  varieties,  the  form  alone  is  suffi- 
cient to  distinguish  it. 

VARIETIES. — The  varieties  of  quartz  owe  their  peculiar- 
ities either  to  crystallization,  mode  of  formation,  or  impuri- 
ties, and  they  fall  naturally  into  three  series. 

I.  The  vitreous  varieties,  distinguished  by  their  glassy 
fracture. 

II.  The  chalcedonic  varieties,  having   a  subvitreous  or 
a  waxy  luster,  and  generally  translucent. 

III.  The  jaspery  varieties,  having  barely  a  glimmering 
faster  and  opaque. 

I.  VITREOUS  VARIETIES. 
Rock  Crystal.     Pure  pellucid  quartz. 
This  is  the  mineral  to  which  the   word  trystal  was   first 
t  applied  by  the  ancients ;  it  is  derived  from  the  Greek  krus- 

What  is  said  of  the  color  and  appearance  of  quartz  ]  How  is  it  dis- 
tinguished ?  What  are  the  three  classes  of  varieties  ?  What  is  the 
Origin  of  the  word  crystal  ? 

12 


134  SILICA. 

tallos,  meaning  ice.  The  pure  specimens  are  often  cut  and 
used  in  jewelry,  under  the  name  of  "  white  stone." 

It  is  often  used  for  optical  instruments  and  spectacle  glass, 
and  even  in  ancient  times  was  made  into  cups  and  vases. 
Nero  is  said  to  have  dashed  to  pieces  two  cups  of  this  kind 
on  hearing  of  the  revolt  that  caused  his  ruin,  one  of  which 
cost  him  a  sum  equal  to  $3000. 

A?nethyst.  A  purple  or  bluish-violet  variety  of  quartz- 
crystal,  often  of  great  beauty.  The  color  is  owing  to  a 
trace  of  oxyd  of  manganese.  It  was  so  called  on  account 
of  its  supposed  preservative  powers  against  intoxication. 
The  amethyst,  especially  when  large  and  finely  colored, 
is  highly  esteemed  as  a  gem.  It  is  always  set  in  gold. 

Rose  Quartz.  A  pink  or  rose -colored  quartz.  It  seldom 
occurs  in  crystals,  but  generally  in  masses  much  fractured, 
and  imperfectly  transparent.  The  color  fades  on  exposure 
to  the  light,  and  on  this  account  it  is  little  used  as  an  orna- 
mental  stone,  yet  is  sometimes  cut  into  cups  and  vases. 
The  color  may  be  restored  by  leaving  it  in  a  moist  place. 

False  Topaz.  This  name  is  applied  to  the  light  yellow 
pellucid  crystals.  They  are  often  cut  and  set  for  topazes. 
The  absence  of  cleavage  distinguishes  it  from  true  topaz. 
The  name  citrine,  often  applied  to  this  variety,  alludes  to  its 
yellow  color. 

Smoky  Quartz.  A  smoky-tinted  quartz  crystal.  The 
color  is  sometimes  so  dark  as  to  be  nearly  black  and  opaque 
except  in  splinters.  Crystals  of  the  lighter  shades  are  often 
extremely  beautiful  and  are  used  for  seals  and  the  less  deli- 
cate kinds  of  jewelry.  It  is  the  cairngorum  stone. 

Milky  quartz.  A  milk-whi'e,  nearly  opaque,  massive 
quartz,  of  very  common  occurrence.  It  has  often  a  greasy 
luster,  and  is  then  called  greasy  quartz. 

Prase.  A  leek-green  massive  quartz,  resembling  some 
shades  of  beryl  in  tint,  but  easily  distinguished  by  the  ab- 
sence of  cleavage  and  its  infusibility.  It  is  supposed  to  be 
colored  by  a  trace  of  iron. 

Aventurine  Quartz.  Common  quartz  spangled  throughout 
with  scales  of  golden-yellow  mica.  It  is  usually  translucent, 
and  gray,  brown,  or  reddish  brown,  in  color.  The  artificial 

What  use  is  made  of  rock  crystal  ?  What  is  the  color  of  amethyst  ? 
Why  was  it  so  called  1  What  is  rose  quartz  1  What  is  said  of  its 
color  1  What  is  false  topaz  1  How  is  it  used  1  What  is  smoky  quartz  ? 
What  is  milky  quartz  ?  What  is  prase  ?  What  is  aventurine  quartz  ? 


QUARTZ.  135 

imitations  of  this  stone  are  more  beautiful  than  the  natural 
aventurinc. 

Ferruginous  Quartz.  Includes  opaque,  yellow,  brownish- 
yellow,  and  red  crystals.  The  color  is  due  to  oxyd  of  iron. 
These  crystals  are  usually  very  regular  in  their  forms,  (fig- 
ure 2,)  and  not  distorted  like  the  limpid  crystals.  They  are 
sometimes  minute  and  aggregated  like  the  grains  of  sand  in  a 
sandstone. 

II.  CHALCEPONIC  VARIETIES. 

Chalcedony.  A  translucent  massive  variety,  with  a  glis- 
tening and  somewhat  waxy  luster  ;  usually  of  a  pale  grayish, 
bluish,  or  light  brownish  shade.  It  often  occurs  lining  or 
filling  cavities  in  amygdaloid  and  other  rocks. 

These  cavities  are  nothing  but  little  caverns,  into  which 
siliciceous  waters  have  filtrated  at  some  period.  The  stalac- 
tites are  "  icicles"  of  chalcedony,  hung  from  the  roof  of  the 
cavity.  Some  of  these  chalcedony  grottos  are  several  feet 
in  diameter. 

Chrysoprase.  An  apple -green  chalcedony.  It  is  colored 
by  nickel. 

Cornelian.  A  bright  red  chalcedony,  generally  of  a  clear 
rich  tint.  It  is  cut  and  polished  and  much  used  in  the  more 
common  jewelry.  The  colors  are  deepened  by  exposure  of 
several  weeks  to  the  sun's  rays.  It  is  often  cut  for  seals  and 
beads.  The  Japanese  cut  great  numbers  into  beads  of  the 
form  of  the  fruit  of  the  olive. 

Sard.  A  deep-brownish  red  chalcedony,  of  a  blood-red 
color  by  transmitted  light. 

Agate.  A  variegated  chalcedony.  The  colors  are  dis- 
|  tributed  in  clouds,  spots,  or  concentric  lines.  These  lines 
I  take  straight,  circular,  or  zigzag  forms  ;  and  when  the  latter, 
it  is  called  fortification  agate,  so  named  from  the  resemblance 
j  to  the  angular  outlines  of  a  fortification.  These  lines  are 
I  the  edges  of  layers  of  chalcedony,  and  these  layers  are  the 
successive  deposits  during  the  process  of  its  formation. 
Mocha  stone  or  Moss  agate  is  a  brownish  agate,  consisting 
of  chalcedony  with  dendritic  or  moss-like  delineations,  of  an 
opaque  yellowish  brown  color.  They  arise  from  dissem- 
inated oxyd  of  iron ;  all  the  varieties  of  agate  are  beau- 

What  is  ferruginous  quartz?  Describe  chalcedony.  What  is  said 
of  its  formation  ?  What  is  chrysoprase  ?  What  is  carnelian  ?  How  is 
its  color  deepened?  For  what  is  it  used  ?  What  is  sard?  Describe 
agate. 


136  SILICA. 

tiful  stones  when  polished,  but  are  not  much  used  in  fine 
jewelry.  The  colors  may  be  darkened  by  boiling  the  stone 
in  oil,  and  then  dropping  it  into  sulphuric  acid.  A  little  oil 
is  absorbed  by  some  of  the  layers,  which  becomes  blackened 
or  charred  by  the  acid. 

Onyx.  This  is  a  kind  of  agate  with  the  colors  arranged 
in  flat  horizontal  layers.  They  are  usually  light  clear  brown 
and  an  opaque  white.  When  the  stone  consists  of  sard 
and  white  chalcedony  in  alternate  layers,  it  is  called  sar- 
donyx. 

Onyx  is  the  material  used  for  cameos,  and  is  well  fitted 
for  this  kind  of  miniature  sculpture.  The  figure  is  carved 
out  of  one  layer  and  stands  in  relief  on  another.  The  most 
noted  of  the  ancient  cameos  is  the  Mantuan  vase  at  Bruns- 
wick. It  was  cut  from  a  single  stone,  and  has  the  form  of  a 
creampot,  about  7  inches  high  and  2£  broad.  On  its  out- 
side, which  is  of  a  brown  color,  there  are  white  and  yellow 
groups  of  raised  figures,  representing  Ceres  and  Triptolemus 
in  search  of  Proserpine.  The  Museo  Borbonico  contains  an 
onyx  measuring  .eleven  inches  by  nine,  representing  the 
apotheosis  of  Augustus  ;  and  another  exhibiting  the  apothe- 
osis of  Ptolemy  on  one  side  and  the  head  of  Medusa  on  the 
other.  Both  are  splendid  specimens  of  the  art,  and  the 
former  is  supposed  to  be  the  largest  in  existence. 

Cat's  eye.  This  is  a  greenish-gray  translucent  chalcedo- 
ny, having  a  peculiar  opalescence,  or  glaring  internal  reflec- 
tions, like  the  eye  of  a  cat,  when  cut  with  a  spheroidal  sur- 
face. The  effect  is  owing  to  filaments  of  asbestus.  It 
comes  from  Ceylon  and  Malabar,  ready  cut  and  polished,  and 
is  a  gem  of  considerable  value. 

Flint,  Hornstone.  Flint  is  massive  compact  silica,  of  dark 
shades  of  smoky  gray,  brown,  or  even  black,  and  feebly  trans- 
lucent. It  breaks  with  sharp  cutting  edges  and  a  conchoid- 
al  surface.  It  is  well  known  as  the  material  of  gun-flints. 
It  occurs  in  nodules  in  chalk  :  not  unfrequently  the  nodules 
are  in  part  chalcedonic.  Hornstone  resembles  flint,  but  is 
more  brittle,  and  therefore  unfit  for  making  into  flints.  It  is 
found  in  limestone,  and  one  of  these  rocks  is  called  cherty 
limestone,  from  the  abundance  of  it. 

Plasma.     This  is  a  faintly  translucent  variety  of  chalcc- 

Hovv  may  the  colors  of  agate  be  deepened  ]  What  is  onyx?  For 
what  is  it  used  ?  What  are  some  of  the  remarkable  canieus  ?  What 
is  cat's  eye  ?  What  is  flint  ?  How  does  it  diiier  from  horaslone. 


QUARTZ.  137 

dony  approaching  jasper,  of  a  greenish  color,  sprinkled  with 
yellow  and  whitish  dots. 
III.  JASPERY  VARIETIES. 

Jasper.  A  dull  red  or  yellow  siliceous  rock,  containing 
some  clay  and  yellow  or  red  oxyd  of  iron.  The  yellow 
jasper  becomes  red  by  heat,  owing  to  its  rendering  the  iron 
anhydrous.  It  also  occurs  of  green  and  other  shades.  Ri- 
band jasper  is  a  jasper  consisting  of  broad  stripes  of  green, 
yellow,  gray,  red  or  brown.  Egyptian  jasper  consists  of 
these  colors  in  irregular  concentric  zones,  and  occurs  in  no- 
dules, which  are  usually  sawn  across  and  polished.  Ruin 
jasper  is  a  variety  with  delineations  like  ruins,  of  some 
brownish  or  yellowish  shade  on  a  darker  ground.  Porcelain 
jasper  is  nothing  but  a  baked  clay,  and  differs  from  jasper  in 
being  fusible  before  the  blowpipe.  Red  porphyry  resembles 
red  jasper;  but  this  is  also  fusible,  and  consists  almost  purely 
of  feldspar. 

Jasper  admits  of  a  high  polish,  and  is  a  handsome  stone 
for  inlaid  work,  but  is  not  used  as  a  gem. 

Bloodstone  or  Heliotrope.  This  is  a  deep  green  stone, 
slightly  translucent,  containing  spots  of  red,  which  have 
some  resemblance  to  drops  of  blood.  It  contains  a  few  per 
cent,  of  clay  and  oxyd  of  iron  mechanically  combined  with 
i  the  silica.  The  red  spots  are  colored  with  iron.  There  is 
a  bust  of  Christ  in  the  royal  collection  at  Paris,  cut  in  this 
stone,  in  which  the  red  spots  are  so  managed  as  to  represent 
drops  of  blood. 

Lydian  stone,    Touchstone,  Basanite.     A  velvet-black  si- 

I  liceous  stone  or  flinty  jasper,  used  on  account  of  its  hardness 

and  black  color  for  trying  the  purity  of  the  precious  metals  ; 

j  this   was  done  by  comparing  the  color  of  the  tracing  left  on 

it  \vith  that  of  an  alloy  of  known  character. 

Besides  the  above  there  are  also  two  or  three  other  varie- 
\  ties,  arising  from  structure. 

Float  stone.  This  variety  consists  of  fibres  or  filaments, 
aggregated  in  a  spongy  form,  and  so  light  as  to  float  in  wa- 
ter. It  comes  from  the  chalk  formations  of  Menil  Montant, 
near  Paris. 

Tabular  quartz.     Consists  of  thin  plates,  either  parallel 
i  or  crossing  one  another  and  leaving  large  open  cells. 

Granular  quartz.  A  rock  consisting  of  quartz  grains 
compactly  cemented.  The  colors  are  white,  gray,  flesh-red, 

What  is  plasma  ?  What  is  jasper  ?  What  is  bloodstone?  Lydian  stone? 
12* 


138  SILICA. 

yellowish  or  reddish  brown.  Sandstone  often  consists  of 
nearly  pure  quartz* 

Silicfad  wood.  Petrified  wood  often  consists  of  quartz. 
Some  specimens,  petrified  with  chalcedony  or  agate,  are 
remarkably  beautiful  when  sawn  across  and  polished,  re- 
taining all  the  texture  or  grain  as  perfect  as  in  the  original 
wood. 

Penetrating  substances.  Quartz  crystals  are  sometimes 
penetrated  by  other  minerals.  Rutile,  asbestus,  actinolite, 
topaz,  tourmaline,  chlorite  and  anthracite,  are  some  of  these 
substances.  The  rutile  often  looks  like  needles  or  fine  hairs 
of  a  brown  color  passing  through  in  every  direction.  They 
are  cut  for  jewelry,  and  in  France  pass  by  the  name  of  Flcches 
d* amour,  (love's  arrows.)  The  crystals  of  Herkirner  county, 
N.  Y.,  often  contain  anthracite.  Other  crystals  contain 
cavities  filled  with  some  fluid,  as  water,  naphtha  or  some 
mineral  solution. 

Loc.  Fine  quartz  crystals  occur  in  Herkimer  county, 
New  York,  at  Middlefield,  Little  Falls,  Salisbury  and  New- 
port,  in  the  soil  and  in  cavities  in  a  sandstone.  The  beds  of 
iron  ore  at  Fowler  and  Hermon,  St.  Lawrence  county,  af- 
ford dodecahedral  crystals.  Diamond  rock  near  Lansing- 
burg  is  an  old  locality,  but  not  affording  at  present  good 
specimens.  Diamond  Island,  Lake  George,  Pelham  and 
Chesterfield,  Mass.,  Paris  and  Perry,  Me.,  and  Meadow  Mt., 
Md.,  are  other  localities.  Small  unpolished  rhombohedrons, 
the  primary  form,  have  been  found  at  Chesterfield,  Mass. 
Rose  quartz  is  found  at  Albany  and  Paris,  Me.,  Acworth, 
N.  H.,  and  Southbury,  Conn.  ;  smoky  quartz  at  Goshen, 
Mass.,  Paris,  Me.,  and  elsewhere  ;  amethyst  at  Bristol,  R.  I., 
and  Kewenaw  Point,  Lake  Superior  ;  chalcedony  and  agates 
of  moderate  beauty  near  Northampton,  and  along  the  trap  of 
the  Connecticut  valley — but  finer  near  Lake  Superior,  upon 
some  of  the  Western  rivers,  and  in  Oregon ;  chryroprase 
occurs  at  Belmont's  lead  mine,  St.  Lawrence  county,  N.  Y., 
and  a  green  quartz  (often  called  chryroprase)  at  New  Fane, 
Vt.,  along  with  fine  drusy  quartz  ;  red  jasper  occurs  on  the 
banks  of  the  Hudson  at  Troy,  and  at  Saugus  near  Boston, 
Mass. ;  yellow  jasper  is  found  with  chalcedony  at  Chester, 
Mass. ;  Heliotrope  occupies  veins  in  slate  at  Blooomingrove, 
Orange  county,  N.  Y. 

What  is  granular  quartz  ?  What  is  said  of  silicified  wood  ?  What 
are  common  penetrating  substances  1 


13TLICA,  139 


OPAL. 

Compact  and  amorphous  ;  also  in  reniform  and  stalactitic 
shapes.  Presents  internal  reflections,  often  of  several  colors, 
and  the  finest  opals  exhibit  a  rich  play  of  colors  of  deli- 
cate shades  when  turned  m  the  hand.  White,  yellow,  red, 
brown,  green  and  gray  are  some  of  the  shades  that  occur, 
and  impure  varieties  are  dark  and  opaque.  Luster  sub- 
vitreous.  H=5'5— 6-5.  Gr,=2*21. 

Composition  ;  opal  consists  of  silica  and  5  to  12  per  cent. 
•of  water, 

VARIETIES. 

Precious  opal,  Noble  opaL  External  color  usually  milky, 
but  within  there  is  a  rich  play  of  delicate  tints.  Composi- 
tion, silica  90,  water  10,  (Klaproth.)  This  variety  forms  a 
gem  of  rare  beauty.  It  is  cut  with  a  convex  surface.  The 
largest  mass  of  which  we  have  any  knowledge  is  in  the  im- 
perial cabinet  of  Vienna  ;  it  weighs  17  ounces,  and  is  nearly 
as  large  as  a  man's  fist,  but  contains  numerous  fissures  and 
is  not  entirely  disengaged  from  the  matrix.  This  stone  was 
well  known  to  the  ancients  and  highly  valued  by  them. 
They  called  it  paideros,  or  child  beautiful  as  Love,  The 
noble  opal  is  found  near  Cashau  in  Hungary,  and  in  Hon- 
duras, South  America ;  also  on  the  Faroe  Islands. 

Fire  opal,  Girasol,  An  opal  with  yellow  and  bright  hya- 
cinth or  fire-red  reflections.  It  comes  from  Mexico  and  the 
Faroe  Islands. 

Common  opal,  Semiopal.  Common  opal  has  the  hardness 
of  opal  and  is  easily  scratched  by  quartz,  a  character  which 
distinguishes  it  from  some  silicious  stones  often  called  semi- 
opal.  It  has  sometimes  a  milky  opalescence,  but  does  not 
reflect  a  play  of  colors.  The  luster  is  slightly  resinous,  and 
the  colors  are  white,  gray,  yellow,  bluish,  greenish  to  dark 
grayish  green.  Translucent  to  nearly  opaque.  Phillips 
found  nearly  8  per  cent,  of  water  in  one  specimen. 

Hydrophane.  This  variety  is  opaque  white  or  yellowish 
when  dry,  but  becomes  translucent  and  opalescent  when  im- 
mersed in  water. 

Cacftolong.     Opaque  white,  or  bluish  white,  and  usual! 


Describe  opal.  How  does  it  differ  from  quartz  in  composition  ?  What 
is  said  of  the  appearance  and  value  of  noble  opal  ?  What  is  fire  opal  1 
common  opal  ? 


140  SILICA* 

associated  with  chalcedony.  Much  of  what  is  so  called  fs 
nothing  but  chalcedony ;  but  other  specimens  contain  water, 
and  are  allied  to  hydrophane.  It  contains  also  a  little  alum- 
ina and  adheres  to  the  tongue.  It  was  first  brought  from 
the  river  Cach  in  Bucharia. 

Hyalite,  Mutter's  glass.  A  glassy  transparent  variety, 
occurring  in  small  concretions  and  occasionally  stalactitic. 
It  resembles  somewhat  a  transparent  gum  arabic.  Com- 
position, silica  92-00,  water  6-33,  (Bucholz.) 

Menilite.  A  brown  opaque  variety,  in  compact  reniform 
masses,  occasionally  slaty.  Composition,  silica  85 '5,  water 
ll'O,  (Klaproth.)  It  is  found  in  slate  at  Menil  Montant, 
near  Paris. 

Wood  opal.  This  is  an  impure  opal,  of  a  gray,  brown  or 
black  color,  having  the  structure  of  wood,  and  looking  much 
like  common  silicified  wood.  It  is  wood  petrified  with  a 
hydrated  silica,  (or  opal,)  instead  of  pure  silica,  and  is  dis- 
tinguished by  its  lightness  and  inferior  hardness.  Specific 
gravity,  2. 

Opal  jasper.  Resembles  jasper  in  appearance,  and  con- 
tains a  few  per  cent,  of  iron  ;  but  it  is  not  so  hard  owing  to 
the  water  it  contains. 

Siliceous  sinter  has  often  the  composition  of  opal,  though 
sometimes  simply  silica.  The  name  is  given  to  a  loose 
porous  siliceous  rock  usually  of  a  grayish  color.  It  is  de- 
posited around  the  Geysers  of  Iceland  in  cellular  or  compact 
masses,  sometimes  in  fibrous,  stalactitic  or  cauliflower-like 
shapes.  Pearl  sinter,  or  fiorite  occurs  in  volcanic  tufa  in 
smooth  and  shining  globular  or  botryoidal  masses,  having  a 
pearly  luster. 

Tdbasheer  is  a  siliceous  aggregation  found  in  the  joints  of 
the  bamboo  in  India.  It  contains  several  per  cent,  of  water, 
and  has  nearly  the  appearance  of  hyalite. 

Dif.  Infusibility  before  the  blowpipe  is  the  best  character 
for  distinguishing  opal  from  pitchstone,  pearlstone,  and  other 
species  it  resembles.  The  absence  of  anything  like  cleav- 
age or  crystalline  structure  is  another  characteristic.  Its 
inferior  hardness  separates  it  from  quartz. 

Obs.  Hyalite  is  the  only  variety  of  opal  that  has  yet 
been  found  in  the  United  States.  It  occurs  sparingly  at  the 


What  is  hyalite  ?  wood  opal  ?  siliceous  sinter  1   tabasheer  1     How  is 
opal  distinguished  from  pitchstone  and  quartz  1 


TABtJLAR   SPAR.  141 

Phillips  ore  bed,  Putnam  county,  N.  Y.,  and  in  Burke  and 
Scrivrn  counties,  Georgia.  The  Suanna  spring  in  Georgia 
atl'urds  siuall  quantities  of  siliceous  sinter. 


2.    LIME. 

The  silicates  and  borosilicate  of  lime  gelatinize  readily 
and  perfectly  with  muriatic  acid.  In  hardness  they  are  nci 
above  feldspar,  (6,J  and  their  specific  gravities  do  not  exceee 
3.  They  fuse  before  the  blowpipe  with  different  degrees  of 
facility,  affording  no  metallic  reaction. 

TABULAR    SPAR. 

TricKnate.  Rarely  in  oblique  rhombotdal  prisms.  Usual- 
ly massive,  cleaving  easily  in  one  direction,  and  showing  a 
lined  or  indistinctly  columnar  surface,  with  a  vitreous  luster 
inclining  to  pearly. 

Usually  white,  but  sometimes  tinged  with  yellow,  red,  or 
brown.  Translucent,  or  rarely  subtransparent.  Brittle. 
11=4—5.  Gr=2-75—  2-9. 

Composition  :  silica  52,  lime  48.  Fuses  with  cUfficulty  to 
a  subtransparent,  colorless  glass  ;  forms  with  borax  a  clear 
glass. 

Dif.  Differs  from  any  carbonates  in  not  effervescing  with 
|  acids  ;  from  asbestus  and  nenaalite  in  its  more  vitreous  ap- 
pearance and  fracture  ;  and  from  these  and  treraoHte  in  its 
forming  a  jelly  with  acids;  from  natrofite,  scolecite  and  dys- 
clasite  in  its  very  broad  s^fr-fibrous  cleavage  surface  and 
more  difficult  fusibility  ;  from  feldspar  in  the  lined  appear- 
ance of  a  cleavage  surface  and  the  action  of  acids. 

•Obs,  Usually  found  in  granite  or  granular  limestone  ; 
occasially  in  basalt  or  lava. 

At  Willsboro',  Lewis,  Diana,  and  Roger's  Rock,  N.  Y., 
it  is  abundant,  of  a  white  color,  along  with  garnet.  At 
Boonville,  it  is  found  in  boulders  with  garnet  and  pyroxene. 
Grenville,  Lower  Canada,  and  Bucks  county,  Pennsylvania, 
are  other  localities.  Occurs  s.lso  at  Kewenaw  Point,  Lake 
Superior. 

What  are  the  prominent  characters  of  the  silicates  and  borosilicate 
<tf  lime  ?  Wkat  is  the  color  and  appearance  of  tabular  spar  ?  Of  what 
does  it  consist?  How  does  it  difler  from  the  carbonates?  how  -from 
asbestos,  treuiolite,  and  feldspar  2 


142  LIME. 


DATHOLITE  —  BorosUicatc  of  Lime, 

Monoclinate.  In  modified  oblique  rhombic  prisms.  M  : 
M=77°  30'.  Crystals  without  distinct  cleavage  ;  small  and 
glassy.  Also  botryoidal,  with  a  columnar  structure,  and  then 
called  boiryoUte.  Color  white,  occasionally  grayish,  green- 
ish, yellowish  or  reddish.  Translucent.  H  =  5  —  5-5. 
Gr=2-9—  3. 

Composition:  silica  37  '4,  lime  35*7,  boracrc  acid  21  '3, 
water  5*7.  Botryolite  contains  twice  the  proportion  of  water. 
Rendered  friable  in  the  flame  of  a  candle.  Before  the  blow- 
pipe  becomes  opaque,  intumesces  and  melts  to  a  glassy 
globule  coloring  the  flame  green.  Forms  a  jelly  easily  Math 
nitric  acid.  • 

Dif.  Its  small  glassy  complex  crystallizations  without 
cleavage  are  unlike  any  other  mineral  that  gelatinizes  with 
acid,  except  some  chabazites,  from  which  it  is  distinguished 
by  tinging  the  blowpipe  flame  green,  and  having  greater 
hardness. 

Obs.  Occurs  in  amygdaloid  and  gneiss.  In  Connecticut, 
the  finest  come  from  Roaring  brook,  14  miles  from  New 
Haven.  The  Rocky  Hill  quarry  near  Hartford,  Berlin,  Mid. 
diefield  Falls,  Conn.,  and  Bergen  Hill  and  Patterson  in  New 
Jersey,  are  other  localities  ;  also  in  great  abundance  at 
Eagle  Harbor  in  the  copper  region,  Lake  Superior. 

Uses.  Where  abundant,  as  near  Lake  Superior,  it  may 
be  profitably  employed  in  the  manufacture  of  boracic  acid'. 
It  is  suggested  by  Dr.  C.  T.  Jackson  as  a  good  flux  for  the 
copper  ores. 

Dysdasite.  In  white  fibrous  seams  or  masses  consisting  of  delicate 
fibers,  and  singularly  tough  under  the  hammer  ;  color  whitish,  yellowish 
or  bluish.  H=4'5.  Gr=2'28  —  2  36.  Composition,  silica  57'0,  time 
26'4,  water  16'6.  Fuses  on  the  edges.  Gelatinizes-  easily  in  muriatic 
acid.  From  the  Faroe  Islands  in  trap.  The  variety  okenite  is  from 
Greenland. 

Pectohte.  Divergent,  fibrous  and  resembling  dysclaslte.  Luster  weak 
pearly.  H=4—  5.  Gr=2  69  Composition,  silica  51'3,  lime  33'  8, 
soda  8'3,  potash  1*6,  water  (hygrometric  '?)  3"  9.  Fuses  to  a  white  trans- 
parent glass.  From  the  Tyrol  and  Fasi-a-thal.  —  A  mineral  fromBergea 
Hill,  which  has  been  called  stellite  is  near  pectolite  in  appearance,  and 
chemical  composition. 


What  is  said  of  the  crystals  of  datholite  ?     How  much  boracic  acid 
does  datholite  contain  I    Haw  is  it  distinguished  1 


TALC.  143 

Edelforsite.  A  fibrous  or  feathery  silicate  of  lime,  consisting  of  silica 
61-8,  lime  38  2.  From  Aedelfors  in  Smalaiid. 

3.    MAGNESIA. 

The  blowpipe  test  for  distinguishing  magnesia  when  not 
disguised  by  the  presence  of  a  metallic  oxyd,  is  given  on 
page  123.  None  of  the  silicates  of  magnesia  gelatinize  with 
acids.  The  species  vary  in  hardness  from  1  to  8.* 

1.  Hydrous  Silicates  of  Magnesia.^ 

TALC, 

Trimetric.  In  right  rhombic  or  hexagonal  prisms.  M  : 
M  =  120°  Usually  in  pearly  foliated  masses,  separating 
easily  into  thin  translucent  folia.  Sometimes  stellate,  or 
divergent,  consisting  of  radiating  laminae  ;  often  massive,  con- 
sisting of  minute  pearly  scales  ;  also  crystalline  granular,  or 
of  a  h'ne  impalpable  texture. 

Luster  eminently  pearly,  and  feel  unctuous.     Color  some 
:  shade  of  light  green  or  greenish  white ;  occasionally  silvery 
;  white  ;  also  grayish  green  and  dark  olive  green.     H  =  1 — 
;  1*5  ;  easily  impressed  with  the  nail.     Gr  =  2*7 — 2*9.     Lam- 
ina? flexible,  but  not  elastic. 
VARIETIES. 

Foliated  talc.  The  purest  talc,  occurring  in  foliated  masses, 
of  a  white  or  greenish  white  color,  and  having  an  unctuous 
feel. 

Soapstone,  or  Steatite.  A  gray  or  grayish  green  massive 
'  talc,  showing  when  broken  a  fine  crystalline  texture. 

Potstone,  or  Lapis  ollaris.  An  impure  talc,  of  grayish 
•  green  and  dark  green  colors  and  slaty  structure.  Feel 
,  unctuous. 

Do  any  silicates  of  magnesia  gelatinize  with  acids?  Describe  talc. 
What  is  steatite  ?  What  is  potstone  1 

*  The  base  magnesia  is  replaceable  by  protoxyd  of  iron,  protoxyd  of 
manganese,  or  lime,  as  illustrated  in  the  species  pyroxene,  and  conse- 
quently this  group  embraces  compounds  which  are  not  purely  silicates 
of  magnesia. 

t  Talc  is  often  anhydrous  ;  but  since  the  discoveries  of  Scheerer  with 
regard  to  the  peculiar  isomorphism  of  water  and  magnesia,  there  is  no 
sufficient  reason  for  removing  this  species  from  chlorite  and  the  allied 
hydrous  species  which  follow. 


144  MAGNESIA, 

Indurated  talc.  A  slaty  talc,  of  compact  texture,  and 
above  the  usual  hardness,  owing  to  impurities.  Feel  some* 
what  unctuous.  This  passes  into  talcose  slate,  still  less- 
pure  and  less  unctuous  in  its  feel,  and  coarser  in  its  slaty 
structure-, 

Rensselaerite.  This  name  has  been  given  by  Professor 
Emmons  to  a  kind  of  soapstone  from  St.  Lawrence,  Jeffer- 
son county,  N.  Y.,  which  has  a  very  compact  structure,  af 
soapy  feel,  slight  transluceney,  and  hardness  3  to  4.  It  oc- 
curs of  white,  yellow,  or  grayish  white  colors,  and  even 
black.  It  works  up  with  a  very  smooth  and  handsome  sur- 
face,-and  is  made  into  inkstands. 

Composition  of  foliated  talc,  silica  62'&,  magnesia  32-47 
with  protoxyd  of  iron  1-6,  alumina  1-0,  water  2-3.  Water 
is  considered  by  some  chemists  an  essential  ingredient,  and 
4  per  £ent.  have  been  detected  in  some  talcs. 

Composition  of  steatite,  silica  63*1,  magnesia  34 '3,  pro- 
toxyd of  iron  2'9f.  Before  the  blowpipe  talc  loses  it  color 
and  fuses  with  great  difficulty. 

Dif.  The  unctuous  feel,  foliated  structure,  and  pearly 
luster  of  talc  are  good  characteristics.  It  differs  from  mica 
also  in  being  inelastic,  although  flexible ;  from  chlorite, 
saponite  and  serpentine  in  yielding  no  water  when  heated 
in  a  glass  tube.  Only  the  massive  varieties  resemble  the  last 
mentioned  species,  and  chlorite  has  a  dark  olive -green  color. 

Obs.  Handsome  foliated  talc  occurs  at  Bridgewater,  Vt,  ^ 
Smithfield,  R.  I. ;  Dexter,  Me. ;  Lockwood,  Newton  ana. 
Sparta,  N.  J.,  and  Amity,  N.  Y.  On  Staten  Island,  near 
the  quarantine,  both  the  common  and  indurated  are  obtained ; 
at  Cooptown,  Md.,  green,  blue  and  rose  colored  talc  occur. 
Steatite  or  soapstone  is  abundant,  and  is  quarried  at  Graf- 
ton,  Vt.,  and  an  adjacent  town  ;  at  Francestown  and  Orford, 
N.  H.  It  also  occurs  at  Keene  and  Richmond,  N.  H. ;  at 
Marlboro  and  New  Fane,  Vt. ;  at  Middlefield,  Mass.  ;  in 
Loudon  county,  Va.,  and  at  many  other  places. 

Uses.  Steatite  may  be  sawn  into  slabs  and  turned  in  a 
lathe.  It  is  used  for  fire  stones  in  furnaces  and  stoves,  and 
for  jambs  for  fire-places.  It  receives  a  polish  after  being 
heated,  and  has  then  a  deep  olive-green  color.  It  is  bored 
out  for  conveying  water,  in  place  of  lead  tubes.  Steatite  is 

How  does  talc  differ  from  mica  1  Of  what  does  talc  consist  1  Why 
is  it  useful  for  fire  stones?  What  other  uses  has  it  1 


CHLORITE.  145 

also  used  in  the  manufacture  of  porcelain  ,  it  makes  the  bis- 
cuit semi-transparent,  but  brittle  and  apt  to  break  with  slight 
changes  of  heat.  It  forms  a  polishing  material  for  serpen- 
tine, alabaster  and  glass ;  and  removes  grease  spots  from 
cloth.  When  ground  up,  it  is  employed  for  diminishing  the 
friction  of  machinery.  Potstone  is  worked  into  vessels  for 
culinary  purposes,  at  Como  in  Lombardy. 

CHLORITE, 

Usually  in  dark  olive -green  masses,  having  a  granular 
texture  :  rarely  in  hexagonal  crystals,  foliated  like  talc  and 
in  radiated  forms.  Luster  a  little  pearly.  Rarely  subtrans- 
parent ;  subtranslucent  to  opaque.  Laminae  inelastic.  H  = 
1*5.  Gr=2'65 — 2*85.  Feel  scarcely  unctuous. 

Composition:  silica  30*4,  alumina  17,  magnesia  34*0, 
protoxyd  of  iron  4'4,  water  12'6.  Fuses  with  difficulty  on 
the  thinnest  edges.  Yields  water  when  heated  in  a  glass 
tube. 

This  species  has  lately  been  subdivided  on  chemical 
grounds,  and  the  name  Ripidolite  applied  to  the  new  species 
instituted. 

Dif.  Its  olive  green  color  and  granular  texture  when 
massive  are  characteristic,  and  the  latter  character  will  dis- 
tinguish it  from  serpentine  and  potstone.  From  talc  and  its 
varieties  it  is  distinguished  also  by  yielding  water  in  a  glass 
tube  ;  from  green  iron  earth  in  its  difficult  fusibility. 

Obs.  Chlorite  and  chlorite  slate,  the  latter  an  impure 
;  slaty  variety,  form  extensive  deposits  in  primitive  regions, 
;  and  the  latter  often  contains  crystals  of  magnetic  iron,  horn- 
blende or  tourmaline. 

Saponite.    Soft  and  almost  like  butter,  but  brittle  on  drying ;  color 

white,  or  tinged  with  yellow,  blue   or  red.     Composition,  silica  45-0, 

,  magnesia  24-7,  alumina  9'3,  peroxyd  of  iron  TO,  potash,  0'7,  water 

.  18-0=98-7.     From  Lizard's  Point,  Cornwall.     It  may  be  kneaded  like 

dough  when  first  extracted. 

SERPENTINE. 

Rarely  in  right  rectangular  prisms.     Cleavage  indistinct. 

Usually  massive  and  compact  in  texture,  of  a  dark  oil  green, 

f  olive-green,  or  blackish-green  color.     Occurs  also  fibrous 

What  effect  has  it  in  porcelain  ?     What  is  the  color  and  usual  appear- 
ance of  chlorite  ?     How  is  chlorite  distinguished  from  green  iron  earth  ? 
What  is  the  color  and  appearance  of  serpentine  1 
13 


146 

and  lamellar.  The  lamellar  varieties  consist  of  thm  fblfa& 
sometimes  separable,  but  brittle  ;  colors  greenish-white,  and" 
light  to  dark-green. 

Luster  weak  ;  resinous,  inclining  to  greasy.  Finer  varie* 
ties  translucent ;  also  opaque.  H=2^ — 4.  May  be  cut 
with  a  knife.  Gr=2'5— 2'6.  Becomes  yellowish-gray  on 
exposure.  Feel  sometimes  a  Iktle  unctuous. 

VARIETIES  AND  COMPOSITION. 

Precious  serpentine.  Purer  specimens  of  a  rich  oil  green 
color,  and  translucent,  breaking  with  a  splintery  fracture. 
It  is  a  beautiful  stone  when  polished.  Composition  :  silica 
42*3,  magnesia  44'2,  protoxyd  of  iron  0*2,  carbonic  acid  Q'9>, 
water  12*4.  Gives  ofFwatef  when  heated  ;  becomes  brown- 
ish-red  before  the  blowpipe,  but  fuses  only  on  the  edges. 

Common  serpentine.  Opaque  of  dark  green  shade&  of 
color. 

Picrolite,  Schiller  asbestus*  A  fibrous  serpentine,  of  an 
olive-green  color,  constituting  seams  in  serpentine.  The 
fibers  are  coarse  or  fine,  and  brittle.  Resembles  some  forms 
of  asbestus,  but  differs  in  its  difficult  fusibility.  Thomson's 
Baltimorite  belongs  here. 

Marmolite.  A  foliated  serpentine,  of  greenish  white  and 
light  green  shades  of  color,  and  pearly  luster,  consisting  of 
thin  folia  rather  easily  separable.  The  folia  are  brittle,  and 
the  variety  is  thus  distinguished  from  talc  and  brucite. 
Composition:  silica  40*1,  magnesia  41*4,  protoxyd  of  iron 
2*7,  water  15-7,  (Shepard.) 

Kerolite.     Near  marmolite,  but  folia  not  separable. 

Dif.  Precious  and  common  serpentine  are  easily  distin- 
guished from  other  green  minerals  by  their  dull  resinous  lus- 
ter and  compact  structure,  in  connection  with  their  softness, 
being  easily  cut  with  a  knife,  and  their  low  specific  gravity, 

Obs.  Serpentine  occurs  as  a  rock,  and  the  several  varie- 
ties mentioned  either  constitute  the  rock  or  occur  in  it. 
Occasionally  it  is  disseminated  through  granular  limestone, 
giving  the  latter  a  clouded  green  color  :  this  is  the  verd  an- 
tique marble. 

Good  Serpentine  is  found  in  the  United  States  at  Phil- 


What  is  the  hardness  of  serpentine  1  Of  what  does  it  consist?  What 
is  precious  serpentine  ?  What  are  the  peculiarities  of  marmolite  and 
kerolite?  How  is  serpentine  distinguished?  How  does  serpentine 
occur  ? 


XEPHRITE.  147 

,  Port  Henry,  Goirrerneur,  Warwick,  N.  Y.  ;  New- 
bun  port,  Westfield,  and  Blandford,  Mass. ;  at  Kellyvale  and 
T\e\v  Fane,  Vt. ;  Deer  Isle,  Maine;  New  Haven,  Conn.; 
Bare  Hills,  Md.",  &c.  Marmolite  and  kerolite,  at  Hoboken, 
N.  J.,  and  Blandford,  Mass.,  The  quarries  of  Milford  and 
New  Haven,  Ct.,  afford  a  beautiful  verd-antique,  and  have 
been  wrought ;  but  the  works  are  now  suspended. 

Uses.  Serpentine  forms  a  handsome  marble  when  pol- 
ished, especially  when  mixed  with  limestone,  constituting 
rerd -antique  marble.  Its  -colors  are  often  beautifully  clouded, 
and  it  is  much  sought  for,  as  a  material  for  tables,  jambs  for 
fire-places,  and  ornamental  in -door  work.  Exposed  to  the 
weather,  it  wears  uneven,  and  soon  loses  its  polish.  Chromic 
iron  .is  usually  disseminated  through  it,  and  increases  the 
variety  of  its  shades.  Dr.  C.  T.  Jackson  of  Boston  has  lately 
shown  that  Epsom  salts  (sulphate  of  magnesia)  may  be  prof- 
itably  manufactured  from  serpentine. 

NEPHRITE. — Jade. 

Massive,  and  very  tough  and  compact ;  greenish  or  bluish 
to  white.  Translucent  to  subtranslucent.  Luster  vitreous. 
H  =6-5— 7-5.  Gr  =  2-9— 3-03. 

Composition  :  contains  silica,  magnesia,  and  some  water, 
with  or  without  alumina,  oxyd  of  iron,  and  lime.  It  varies 
in  constitution,  and  has  been  lately  considered  a  massive 
tremolite.  Infusible  alone  before  the  blowpipe. 

Dif.  Differs  from  beryl  in  having  no  cleavage  ;  and  from 
quartz  by  its  finely  uneven  surface  of  fracture,  instead  of 
|  smooth  and  glassy, 

Obs.     A  sky-blue  variety  of  nepTirite  occurs  at  Smithfield, 
,  R.  I.,  and   a  greenish  and   reddish-gray  variety  is  found  at 
Easton,  Pa.,  and  Stoneham,  Mass. 

Nephrite  is  made  into  images,  and  was  formerly  worn  as 
a  charm.  It  was  supposed  to  be  a  cure  for  diseases  of  the 
kidney,  whence  the  name,  from  the  Greek  nephros,  kidney. 
In  New  Zealand,  China  and  Western  America,  it  is  carved 
by  the  inhabitants  or  polished  down  into  various  fanciful 
shapes.  Much  of  the  mineral  from  China  called  jade  is 
1  prehnite. 


What  is  verd-antique  1     What  are  the  uses  of  serpentine  ?     What 
*re  the  characters  of  nephrite  1     What  is  the  origin  of  the  name? 


148  MAGNESIA. 

MEERSCHAUM. — Sea  FrotJt. 

Dull  white,  opaque  and  earthy,  nearly  like  clay.  H=2 
Gr=2-6— 3-4. 

Composition  of  a  variety  from  Anatolia :  silica  42,  mag- 
nesia  30*5,  water  23,  lime  2-3,  alumina  2,  (Thomson.) 
When  heated  it  gives  out  water  and  a  fetid  odor,  and  be- 
comes  hard  and  perfectly  white.  When  first  dug  up  it  is 
soft,  has  a  greasy  feel  and  lathers  like  soap ;  and  on  this 
account  it  is  used  by  the  Tartars  in  washing  their  linen.  It 
is  used  f<jr  making  the  bowls  of  Turkish  pipes,  by  a  process 
like  that  for  pottery  ware.  When  imported  into  Germany, 
the  bowls  of  the  pipes  are  prepared  for  sale  by  softening 
them  first  in  tallow,  then  in  wax,  and  finally  polishing  them. 

Aphrodite  is  another  meerschaum  from  Longbanshyttan. 

Quincite  is  a  variety  or  related  species  of  a  reddish  color. 

SCHILLER    SPAR. 

Triclinate.  Occurs  massive,  with  cleavage  in  two  direc- 
tions, producing  a  thin  foliated  structure.  Folia  brittle  and 
separable.  Color  olive  and  blackish-green,  inclining  on  the- 
cleavage  face  to  pinchbeck-brown.  Luster  metallic-pearly 
on  a  cleavage  face  ;  vitreous  in  other  directions.  H  =  3'5 — 
4.  Sectile.  Gr=2-5 — 2-7. 

Composition:  silica  43' 9^  magnesia  25*9,  oxyd  of  iron  and 
chromium  13'0,  water  12*4,  alumina  1*3,  lime  2'6,  protoxyd 
of  manganese  0§5.  Gives  off  water,  and  becomes  pinch- 
beck-brown and  magnetic  before  the  blowpipe,  but  fuses 
only  on  the  thinnest  edges. 

Dif.  Distinguished  from  diallage,  which  also  occurs  irf 
serpentine,  and  is  the  only  species  with  which  it  can  be 
confounded,  by  its  yielding  water  before  the  blowpipe. 
Marmolite  is  much  softer.  Talc  and  mica  are  flexible. 

Obs.  Occurs  imbedded  in  serpentine.  Baste  in  the  Hartz 
is  a  foreign  locality.  Blandford  and  Westfield,  Mass.,  and 
Amity,  N.  Y.,  are  given  as  American  localities. 

Clintonite.  In  oblique  crystals :  but  usually  massive,  thin  foliated, 
and  brittle,  with  a  submetallic  luster,  and  reddish  or  yellowish-brown,. 
or  copper-red  color.  Streak  yellowish-gray.  Composition,  silica  17'0, 
alumina  37'6,  magnesia  24-3,  lime  10-7,  protoxyd  of  iron  5-0,  water 

What  is  meerschaum  ?  its  appearance  1  What  is  the  structure  of 
^chiller  spar  ?  its  luster  ?  What  does  it  occur  with  1  How  does  u 
differ  from  diallage  1 


SCHILLER    SPAR.  149 

3-6,  (Clemson.)  Infusible.  Affords  a  transparent  bead  with  borax, 
Acied  on  by  the  acids  when  pulverised.  Occurs  in  limestone  with  ser- 
pentine at  Amity,  N.  Y.  It  was  named  in  honor  of  De  Witt  Clinton. 
It  has  also  been  called  Seybertitc. 

Xanthophyllite  is  considered  by  Rose,  its  describer,  as  identical  with 
!  Clintonite. 

Pennine.  Near  chlorite ;  occurs  in  hexagonal  tables,  secondary  to 
a  rhombohedron  of  118°.  From  the  Pennine  Alps. 

Picrosmine.  A  green  or  greenish-white  mineral,  either  fibrous  like 
ssbestus, or  in  rectangular  prisms.  H=2'5— 3.  Gr=2*59 — 2-7.  Gives 
out  water  when  heated,  and  has  an  argillaceous  odor  when  moistened 
with  the  breath.  Near  serpentine  in  composition.  From  an  iron  mine 
in  Bohemia. 

Monradite  is  a  cleavable  yellowish  mineral  near  picrosmine  in  com- 
position. 

Rttinalitc.  A  massive  mineral,  having  a  resinous  appearance,  found 
;  with  and  allied  to  serpentine.  From  Granville,  Upper  Canada. 

Dermatine.  Occurs  massive,  reniform  or  in  crusts  on  serpentine,  of  a 
•  resinous  luster  and  green  color.  Feel  greasy.  Odor  when  moistened 
I  argillaceous. 

Villarsite.  Occurs  in  yellowish  rhombic  octahedrons  in  dolomite  at 
i  Traversella,  in  Piedmont.  Allied  in  composition  to  serpentine. 

Antigorite.  A  brownish  or  leek  green  mineral,  in  foliated  masses  and 
resembling  Schiller  spar, 

Spadaite.     A  flesh-red  mineral,  near  Schiller  spar. 

Pyrallolite.  A  white  or  greenish  cleavable  mineral,  dull  and  a  little 
resinous  in  luster.  Becomes  black  and  then  white  again  before  the 
blowpipe,  whence  the  name,  from  the  Greek  pyr,  fire,  allos,  other,  and 
lithos,  stone.  From  Pargas,  Finland. 

Pyrosclerite.  A  hydrous  silicate  of  magnesia  and  alumina,  of  a  light 
green  color.  From  Elba.  ^ 

Kammererite.  A  related  species,  occuring  in  six-sided  prisms,  red- 
dish violet  within.  Transverse  cleavage,  perfect.  H=2.  Gr=2'76. 

Pyrophyllite.  Foliated  and  pearly  like  talc  ;  plates  more  or  less 
radiating  ;  very  soft.  Color  white  or  greenish.  It  swells  up  and  spreads 
out  in  fan-like  shapes  before  the  blowpipe.  Occurs  in  the  Urals. 

Yermiculite  is  probably  identical  with  pyrophyliite.  It  looks  and 
feels  like  steatite  ;  but  when  heated  before  the  blowpipe,  worm-like 
projections  shoot  out,  owing  to  a  separation  of  the  thin  leaves  composing 
the  grains,  arising  from  the  vaporization  of  the  water  present.  Occurs 
at  Milbury,  Massachusets. 

Periclase.  Occurs  at  Vesuvius  in  small  transparent  octahedrons, 
and  is  supposed  to  be  pure  magnesia.  Luster  vitreous ;  nearly  as  hard 
as  feldspar.  Gr=3'75. 

Steatitic  pseudomorphs.  Pseudomorphous  crystals  often  consist  of  a 
kind  of  steatite.  A  pseudomorph  of  this  kind  from  Warwick,  N.  Y., 
having  the  form  of  hornblende,  but  so  soft  as  to  be  easily  cut  with  a 
knife,  afforded  Beck,  silica  34  7,  alumina  25  3,  lime  5-1,  magnesia  25'2, 
water  9  1.  These  crystals  have  been  produced  by  a  change  of  the 
original  hornblende.  Others  have  the  form  of  spinel,  &c. 

The  Eensselaerite  of  Emmons  is  believed  to  be  a  steatitic  pseudd- 
morph,  or  altered  pyroxene. 

13* 


150  MAGNESIA, 

2.     Anhydrous  Silicates  of  Magnesia)  and  Compounds 
Isormorphous  with  them. 

PYROXENE. 

Monoclinate.  In  modified  oblique  rhombic  prisms  ;  M  : 
87°  6'.  Cleavage  perfect  parallel  with  the  sides  of  the 
prisms,  and  also  distinct  parallel  with  the  diagonals. 
Usually  in  thick  and  stout  prisms,  of  6  or  8  sides, 
terminating  in  two  faces  meeting  at  an  edge  ;  a  ; 
a=  120°  39',  M:  e  =  133°  33,  M  :,e  =  136D  27', 
Occurs  also  in  oblique  octahedrons,  much  modified. 
Massive  varieties  of  a  coarse  lamellar  structure  ; 
also  fibrous,  usually  very  fine  and  often  long  capillary ;  also 
granular,  usually  in  coarse  angular  grains  and  friable,  some- 
times round  ;  sometimes  fine  and  compact. 

Colors  green  of  various  shades,  verging  to  white  on  one 
side  and  brown  and  black  on  the  other,  passing  through  blue 
shades,  but  not  yellow.  Luster  vitreous,  inclining  to  resin- 
ous or  pearly;  the  latter  especially  in  fibrous  varieties. 
Transparent  to  opaque.  H=5 — 6.  Brittle.  Gr  =  3*2 — 
3-5. 

Pyroxene  consists  of  silica  and  magnesia,  combined  with 
one  or  more  of  the  bases,  lime,  protoxyd  of  iron,  or  protoxyd 
of  manganese.  These  bases  replace  one  another  in  a  com- 
pound without  changing  the  crystalline  form,  and  have  the 
same  form  nearly  in  their  own  crystallizations,  as  explained 
on  page  74.  The  varieties  of  pyroxene  arise  from  the  va- 
riations in  composition  dependent  on  this  isomorphism,  and 
they  differ  much  in  appearance. 

Varieties  and  Composition.  The  varieties  may  be  divided 
into  three  sections — the  light  colored,  the  dark  colored,  and 
the  thin  foliated. 

I.  White  malacolite  or  white  augite — includes  white  or 
grayish-white  crystals  or  crystalline  masses.  Diopside  ;  in 
greenish-white  or  grayish-green  crystals,  and  cleavable 
masses  cleaving  with  a  bright  smooth  surface.  Sahlite  ;  of 
a  more  dingy  green  color,  less  luster  and  coarser  structure 
than  diopside,  but  otherwise  similar  ;  named  from  the  place 

What  is  the  character  of  the  crystals  of  pyroxene  ?  What  is  a  com- 
mon form?  What  is  said  of  its  massive  varieties?  its  colors  and  lus- 
ter? What  are  the  constituents  of  pyroxene? 


PYROXEXE.  151 

Sahla,  where  it  occurs.  Fassaite ;  in  crystals  of  rich  green 
shades  and  smooth  and  lustrous  exterior.  The  name  is  de- 
rived from  the  foreign  locality  Fassa.  Alalite ;  a  diopsidc 
from  Piedmont.  Coccolite  is  a  general  name  for  granular 
varieties,  derived  from  the  Greek  coccos,  grain.  The  green 
is  called  green  coccolite,  the  white,  white  coccolite.  The 
specific  gravity  of  these  varieties  varies  from  3'25  to  3*3. 

Composition  :  silica  55 '3,  lime  27-0,  magnesia  17'0,  pro- 
toxyd  of  manganese  1*6,  protoxyd  of  iron  2*2.  Fuse  before 
the  blowpipe  to  a  colorless  glass  ;  with  borax  or  soda  form  a 
transparent  glass. 

Asbestus.  This  name  includes  fibrous  varieties  of  both 
pyroxene  and  hornblende ;  it  is  more  particularly  noticed 
under  the  latter  species. 

II.  Augite    includes  black  and    greenish-black  crystals, 
mostly  presenting  the  form  figured  above.     Specific  gravity 
3' 3 — 3*4.     Hedenbergite  is  a  greenish-black  opaque  variety, 
in    cleavable    masses    affording    a  greenish-brown  streak. 
Specific  gravity  3*5.     Polylite,  Hudsonite,  and  Jeffersonite 
fall  here. 

The  varieties  in  this  section  contain  a  large  proportion  of 
iron  or  iron  and  manganese.  Composition  of  one  variety, 
silica  54-1,  lime  23-5,  magnesia  11*5,  protoxyd  of  iron  10-0, 
protoxyd  of  manganese  0*6  =  99'7.  Fuse  like  the  prece- 
ding, but  the  globule  obtained  is  colored  with  iron. 

III.  Diallage  is  a  thin-foliated,  clear  green  variety,  occur- 
ring imbedded  in  serpentine  ;  folia  thin,  brittle,  translucent. 
Bronzite  occurs  in  serpentine  and  greenstone,  and  is  similar- 
ly foliated ;  its  colors  are  dark  green,  or  greenish  brown, 
with  a  metallic-pearly  luster,  or  like  bronze.     Specific  grav- 
ity 3*25.     Hypersthene  is  less  thinly  foliated  than  bronzite, 
but  cleaves  readily ;  color  grayish  or  greenish  black,  and 
luster  metallic-pearly  Gr=2'39.     The  Labrador  hornblende, 
and  MetaUoidal  diallage  are  here  included. 

Composition  of  hypersthene,  silica  54*25,  lime  1*5,  magne- 
sia 14*0,  protoxyd  of  iron  24'5,  protoxyd  of  manganese  a 
trace,  alumina  2*25,  water  1*0.  The  edges  fuse  with  diffi- 
culty to  a  grayish  green  semi-opaque  glass  ;  some  varieties 
wholly  fuse.  Other  hypersthenes  contain  much  less  iron  and 
a  large  proportion  of  lime. 

Dif.     Resembles  hornblende,  but  is  distinct  in  cleavage 

What  is  coccolite  ?  What  is  the  appearance  of  asbestus  ?  What 
is  diallage?  What  is  hypersthene  ? 


ri* 


152  MAGNESIA. 

and  in  the  angles  of  its  crystals.  Moreover,  the  crystals  are 
usually  stout  and  thick,  and  never  have  the  slender  bladed 
form  common  with  hornblende.  Some  fibrous  varieties, 
however,  can  scarcely  be  distinguished  except  by  analysis  ; 
yet  it  is  a  general  fact,  that  asbestus  occurring  where  pyrox- 
ene abounds,  belongs  to  this  species,  and  that  with  hornblende 
pertains  to  hornblende.  White  crystals  of  scapolite  may  be 
mistaken  for  this  species,  especially  where  two  of  the  pyra- 
midal faces  in  a  crystal  of  scapolite  are  enlarged  so  as  to 
resemble  the  oblique  roof-like  termination  of  crystals  of  py- 
roxene ;  but  the  angle  between  these  faces  in  the  former  is 
136°  T,  while  it  is  120°  39  in  pyroxene.  Their  relations 
to  schiller  spar  and  serpentine  have  already  been  stated. 
The  species  is  never  yellowish  green  like  epidote. 

Obs.  Pyroxene  is  one  of  the  most  common  minerals. 
It  occurs  in  granite,  granular  limestone,  serpentine,  basalt 
and  lavas.  In  basalt  and  lavas  the  crystals  are  generally 
small  and  black  or  greenish  black.  In  the  other  rocks,  they 
occur  of  all  the  shades  of  color  given,  and  of  all  sizes  to  a 
foot  or  more  in  length.  One  crystal  from  Orange  county, 
measured  6  inches  in  length,  and  10  "in  circumference. 
White  crystals  occur  at  Canaan,  Conn.,  Kingsbridge,  New 
York  county,  and  the  Singsing  quarries,  Westchester  coun- 
ty, N.  Y.,  in  Orange  county  at  several  localities;  green 
crystals  at  Trumbull,  Ct.,  at  various  places  in  Orange  coun- 
ty, N.  Y.,  Roger's  Rock  and  other  localities  in  Essex,  Lew- 
is, and  St.  Lawrence  Go's.  Dark  green  or  black  crystals 
are  met  with  near  Edenville,  N.  Y.,  Diana,  Lewis  county. 
Green  coccolite  is  found  at  Roger's  Rock,  Long  Pond,  and 
Willsboro,  N.  Y. ;  black  coccolite,  in  the  forest  of  Dean, 
Orange  county,  N.  Y.  Diopside,  at  Raymond  and  Rumford, 
Me.,  Hustis's  farm,  Phillipstown,  N.  Y. 

Pyroxene  was  thus  named  by  Hauy  from  the  Greek  pur 
fire,  andxenos  stranger,  in  "allusion  to  its  occurring  in  lavas, 
where,  according  to  a  mistake  of  Hafiy,  it  did  not  belong. 
The  name  augite  is  from  the  Greek  auge,  luster. 

HORNBLENDE. 

Monoclinate.      In   oblique    rhombic    prisms     more     or 

What  is  said  of  the  occurrence  of  pyroxene  ?  How  does  it  differ 
from  hornblende  1  how  from  scapolite  1  What  is  the  derivation  of  the 
names  pyroxene  and  augite. 

I 


HORNBLENDE. 


153 


less  modified;  M  :  M  =  124°  30'. 
allel  with  the  sides  of  the  prism.  Of- 
ten in  long  slender  flat  rhombic  prisms, 
(fig.  3)  breaking  easily  transversely  ;  also 
4,  6,  and  8  sided  prisms  with  oblique  ex- 
tremities, e  :  e=  148°  30 .  Occurs  also 
frequently  columnar,  with  a  bladed  struc- 
ture ;  often  fibrous,  the  fibers  coarse  or 
fine  and  frequently  like  flax,  with  a  pearly 
or  silky  luster ;  also  lamellar ;  also  granu- 
lar, either  coarse  or  fine  ;  generally  firmly 
compact ;  rarely  friable. 


Cleavage  perfect 
1 


Colors  from  white  to  black  passing  through  bluish  green, 
grayish  green,  greemf-and  brownish  green  shades,  to  black. 
Luster  vitreous,  with  the  cleavage  face  inclining  to  pearly. 
Nearly  transparent  to  opaque.  H  =  5 — 6.  Gr  =  2'9 — 3.4. 

Varieties  and  Composition.  This  species,  like  pyroxene, 
has  numerous  varieties,  differing  much  in  external  appear- 
ance, and  arising  from  the  same  causes — isomorphism  and 
crystallization.  Alumina  enters  into  the  constitution  of  some 
and  replaces  part  of  the  other  ingredients.  The  following 
are  the  most  important : 

1.  LIGHT  COLORED  VARIETIES. 

Tremolite,  Grammatite.  Tremolite  comprises  the  white, 
grayish,  and  light  greenish  slender  crystallizations,  usually 
in  blades  or  long  crystals,  penetrating  the  gangue  or  aggre- 
gated into  coarse  columnar  forms.  Sometimes  nearly  trans- 
parent. Gr  =  2'93.  The  name  is  from  the  foreign  locality, 
Tremola  in  Switzerland. 

Actinolite.  The  light  green  varieties.  Glassy  actinolite 
includes  the  bright  glassy  crystals,  of  a  rich  green  color,  usu- 
ally long  and  slender  (fig.  3)  and  penetrating  the  gangue 
like  tremolite.  Radiated  actinolite  includes  olive  green 
masses,  consisting  of  aggregations  of  coarse  acicular  fibers, 
radiating  or  divergent.  Asbestiform  actinolite  resembles  the 
radiated,  but  the  fibers  are  more  delicate.  Massive  actino- 
lite consists  of  angular  grains  instead  of  fibers.  Gr  =  3'02 
— 3'03.  The  name  actinolite  alludes  to  the  radiated  struc- 


What  is  the  crystallization  of  hornblende  1  What  are  common  forms? 
What  is  said  of  the  columnar  and  fibrous  varieties?  What  are  its  col- 
ors'? On  what  do  the  characters  of  its  varieties  depend  ?  What  is  tre- 
molite ?  what  actinoiite  ?  Mention  the  characters  of  the  varieties  of 
actinolite  ? 


154  MAGNESIA. 

tare  of  some  varieties,  and  is  derived  from  the  Greek  dktin, 
a  ray  of  the  sun.  It  is  often  mispelt  actynolite. 

Asbestus.  In  slender  libers  easily  separable,  and  some- 
times like  flax.  Either  green  or  white.  Amianthus  in- 
cludes the  asbestus  that  occurs  in  narrow  seams,  with  a  rich 
satin  luster.  Ligniform  asbestus  is  compact  and  hard  ;  it 
occurs  of  brownish  and  yellowish  colors,  and  looks  somewhat 
like  petrified  wood.  Mountain  leather  occurs  in  thin  tough 
sheets,  looking  and  feeling  a  little  like  kid  leather.  It  con- 
sists of  interlaced  fibers  of  asbestus,  and  forms  thin  seams 
between  layers  or  in  fissures  of  rocks.  Mountain  cork  is 
similar,  but  is  in  thicker  masses ;  it  has  the  elasticity  of 
cork,  and  is  usually  white  or  grayish-white. 

The  preceding  light  colored  varieties  contain  little  or  no 
alumina  or  iron.  Composition  of  glassy  actinolite,  silica 
59-75,  magnesia  21'1,  lime  14'25,  protoxyd  of  iron  3*9,  pro- 
toxyd  of  manganese  0'3,  hydrofluoric  acid  0'8,  (Bonsdorf.) 

2.  DARK  COLORED  VARIETIES. 

Pargasite.  This  name  is  applied  to  dark  green  crystals, 
short  and  stout,  (resembling  fig.  1,)  with  bright  luster,  of 
which  Pargas  in  Finland  is  a  noted  locality.  Gr  =  3'll. 

Hornblende.  The  black  and  greenish-black  crystals  and 
massive  specimens.  Often  in  slender  crystallizations  like  acti- 
nolite ;  also  short  and  stout  like  figures  1  and  2,  the  latter  more 
especially.  It  contains  a  large  per-centage  of  oxyd  of  iron, 
and  to  this  owes  its  dark  color.  It  is  a  tough  mineral,  as  is 
implied  in  the  name  it  bears.  This  character  however  is 
best  seen  in  the  massive  specimens.  Pargasite  and  horn- 
blende contain  both  alumina  and  iron. 

Composition  of  hornblende,  silica  48 '8,  magnesia  13'6, 
lime  10*2,  alumina  7*5,  protoxyd  of  iron  18*75,  protoxyd  of 
manganese  1*15,  hydrofluoric  acid  and  water  0.9,  (Bons- 
dorf.) 

Composition  of  pargasite,  silica  46*3,  magnesia  19*0,  lime 
14'0,  alumina  11*5,  protoxyd  of  iron  3'5,  protoxyd  of  man- 
ganese 0*4,  hydrofluoric  acid  and  water  2*2. 

Amphibole  is  a  name  often  given  to  this  species. 

The  varieties  of  hornblende  fuss  easily  with  some  ebulli- 
tion, the  white  varieties  forming  a  colorless  glass  and  the 
green  a  globule  more  or  less  colored  by  iron. 

What  is  asbestus  and  amianthus'?  mountain  leather  and  mountain 
C£>rk  1  What  is  the  peculiaiity  in  composition  of  the  light  colored  va- 
rieties of  hornblende  ]  what  of  the  dark  varieties  1 


HOllXBLEM'l..  155 

Dif.  Distinguished  from  pyroxene  as  stated  under  thai 
species ;  the  black  variety  from  black  tourmaline  by  its  per- 
fect cleavage,  (tourmaline  having  none,)  and  also  by  the 
form  of  its  crystals  ;  the  fibrous  varieties  from  picrosmine, 
nemalite,  and  tabular  spar,  as  stated  under  those  species ; 
from  the  fibrous  zeolites  by  not  gelatinizing,  and,  when 
in  limestone  or  serpentine,  by  its  gangue. 

Obs.  Hornblende  is  an  essential  constituent  of  certain 
rocks,  as  syenite,  trap  and  hornblende  slate.  Actinolite  is 
usually  found  in  magnesian  rocks,  as  talc,  steatite  or  serpen- 
tine ;  tremolite  in  granular  limestone  and  dolomite  ;  asbes- 
tus  in  the  above  rocks  and  also  in  serpentine.  Black  crys- 
tals of  hornblende  occur  at  Franconia,  N.  H.,  Chester,  Mass., 
Thomaston,  Me.,  Willsboro',  N.  Y.  in  Orange  county,  N. 
Y.,  and  elsewhere.  Pargasite  occurs  at  Phipsbufg  and  Par- 
sonsfield,  Me. ;  glassy  actinolite,  in  steatite  or  talc,  at  Wind- 
ham,  Readsboro',  and  New  Fane,  Vt.,  Middlefield  and  Bland- 
ford,  Mass. ;  and  radiated  varieties  at  the  same  localites  and 

.  many  others.  Tremolite  and  gray  hornblende  occur  at  Ca- 
naan, Ct.,  Lee,  Ncwburgh,  Mass.,  in  Thomaston  and  Ray- 
mond, Me.,  Lee  and  Great  Barrington,  Mass.,  Dover,  Kings- 
bridge,  and  in  St.  Lawrence  county,  N.  Y.,  at  Chesnut  Hill, 
Penn.,  at  the  Bare  Hills,  Md.  Asbestus  at  many  of  the 
above  localities ;  also  at  Milford,  Conn.,  Brighton  and  Shef- 
field, Mass.,  Cotton  Rock  and  Hustis's  farm,  Phillipstown, 

f  N.  Y.,  near  the  quarantine,  Richmond  county,  N.  Y.  Moun- 
tain leather  is  met  with  at  the  Milford  quarries,  and  also  at 
Brunswick,  N.  J. 

Uses.     Asbestus  is  the  only  variety  of  this  species  of  any 

I  use  in  the  arts.     The   flax-like   variety  is   sometimes  wo- 

i  ven  into  cloth  ;  it  has  been  proposed  of  late  to  use  clothes 
of  it  for  firemen,  and  patents  have  been  taken  out.  Its  in- 

i  combustibility  and  slow  conduction  of  heat,  render  it  a  com- 
plete protection  against  the  flames.  It  is  often  made  into 
gloves.  A  garment  when  dirty,  need  only  be  thrown  into 
the  fire  for  a  few  minutes  to  be  white  again.  The  ancients, 
who  were  acquainted  with  its  properties,  are  said  to  have 
used  it  for  napkins,  on  account  of  the  ease  with  which  it 
was  cleaned.  It  was  also  the  wicks  of  the  lamps  in  the  an- 

\  cient  temples ;  and  because  it  maintained  a  perpetual  flame 

How  does  the  species  hornblende  differ  from  tourmaline  and  other 
minerals  mentioned  ?  What  is  said  of  the  occurrence  of  hornblende  ? 
What  are  the  uses  of  asbestus  ?  Why  was  it  so  called  I 


156  MAGNESIA. 

without  being  consumed,  they  named  it  asbestos,  uncon- 
sumed.  It  is  now  used  for  the  same  purpose  by  the  native 
of  Greenland.  The  name  amianthus  alludes  to  the  ease  of 
cleaning  it,  and  is  derived  from  amiantos,  undefiled.  Asbes- 
tus  is  now  extensively  used  for  lining  iron  safes.  The  best 
locality  for  collecting  asbestus  in  the  United  States,  is  that 
near  the  quarantine,  in  Richmond  county,  N.  Y. 

Anthophyllite.  In  oblong  grayish,  greenish,  or  brownish  crystals,  or 
in  needles,  imbedded  in  mica  slate,  or  penetrating  it.  Cleavage  paral- 
lel to  the  lateral  surfaces  of  a  rhombic  prism,  and  also  to  both  diago- 
nals. Brittle  ;  fibers  sharp.  Gr=2'9— 3'16.  Resembles  hornblende, 
and  may  be  a  variety  of  it.  Occurs  at  Hacldam  and  Guilford,  Conn., 
and  Chesterfield,  Chester,  and  Blandford,  Mass. 

Cummingtonite.  Fibrous  ;  the  fibers  divergent,  stellular  or  scopi- 
form.  Rather  incoherent.  Color  ash-gray.  Luster  a  little  silky. 
Translucent tt>  opaque.  H=6 — 6'5.  Gr=3'2.  Considered  a  variety 
of  hornblende.  From  Cummington  and  Plainfield,  Mass.,  in  mica 
slate. 

CHRYSOLITE. — Olivine. 

Trimetric.  In  right  rectangular  prisms,  having  perfect 
cleavage  parallel  with  the  smaller  lateral  plane.  Usually 
in  imbedded  grains  of  an  olive  green  color,  looking  like  green 
bottle  glass.  Also  yellowish-green.  Transparent  to  trans- 
lucent. H  =  6'5 — 7.  Gr  =  3'3 — 3-5.  Looks  much  like 
glass  in  the  fracture,  except  in  the  direction  of  the  cleavage. 

Composition :  silica  38*5,  magnesia  48'4,  protoxyd  of 
iron  11*2,  oxyd  of  manganese  0*3,  alumina  0'2.  Darkens 
before  the  blowpipe  but  (except  certain  varieties)  does  not 
fuse.  Forms  a  green  glass  with  borax. 

Dif.  Distinguished  from  green  quartz  by  its  occurring 
disseminated  in  basaltic  rocks,  which  never  so  occurs  ;  also 
in  its  cleavage.  On  account  of  its  gangue  it  cannot  be  mis- 
taken for  beryl.  From  obsidian  or  volcanic  glass  it  differs 
in  its  infusibility. 

Obs.  Occurs  disseminated  through  basalt  and  lavas, 
and  is  a  characteristic  mineral  of  some  varieties  of  these 
rocks. 

Uses.  Sometimes  used  as  a  gem,  but  it  is  too  soft  to  be 
valued,  and  is  not  delicate  in  its  shade  of  color. 

What  is  the  crystallization  of  chrysolite  ?  what  is  its  color  and  appear- 
ance ?  How  does  it  act  before  the  blowpipe  1  of  what  does  it  consist  1 
What  is  its  mode  of  occurrence  ?  How  does  it  differ  from  green 
quartz  1  from  obsidian  or  volcanic  glass  1 


CUOXDRODITE.  157 


CHONDRODITE. 

Usually  in  imbedded  grains  or  small  rounded  or  flattened 
kernels  or  nodules  in  limestone,  and  appearing  brittle 
Structure  finely  granular  without  cleavage.  Color  brownish 
yellow,  or  brown ;  sometimes  reddish  or  greenish,  and  oc- 
casionally black.  Luster  vitreous,  inclining  a  little  to  resin- 
ous. Streak  rarely  colored.  Translucent  or  subtranslucent. 
Fracture  uneven.  H=6 — 6*5.  Gr  =  3'l — 3'2. 

Composition  :  silica  33' 1,  magnesia  55*5,  protoxyd  of  iron 
3*6,  fluorine  7'6.  From  New  Jersey.  Fuses  with  difficulty 
on  the  edges.  With  borax  fuses  easily  to  a  yellowish-green 
glass. 

Dif.  As  it  occurs  only  in  limestone  it  will  hardly  be  con- 
founded with  any  species  resembling  it  in  color  when  the 
gangue  is  present.  The  specific  gravity  is  less  than  that  of 
tourmaline  or  garnet,  some  brownish-yellow  varieties  of 
which  it  approaches  in  appearance  ;  moreover,  it  is  seldom 
in  crystals,  and  when  so,  the  faces  are  not  polished.  This 
mineral  has  been  called  Brucite ;  but  chondrodite  is  of 
prior  authority  ;  it  is  from  the  Greek  chondros,  a  grain. 

Obs.  Has  been  found  only  in  granular  limestone.  It  is 
abundant  in  the  adjoining  counties,  Sussex  N.  J.  and  Orange, 
N.  Y.,  occurring  at  Sparta,  and  Bryam,  N.  J.,  and  in  War- 
wick  and  other  places  in  J»Jew  York. 

Arfwedsonite.  Resembles  black  hornblende  and  occurs  massive  with 
one  eminent  cleavage.  Gr=3  2 — 3'4.  Perhaps  a  variety  of  horn- 
blende. From  Greenland. 

Acmite.  In  long  highly  polished  prisms,  of  a  dark  brown  or  reddish- 
brown  color,  with  a  pointed  extremity,  penetrating  granite,  near  Kongs- 
berg  in  Norway.  M  :  M=86°  56'.  Resembles  pyroxene  and  may  be 
a  variety  of  that  species.  Fuses  easily  before  the  blowpipe. 

Babingtonite.  Resembles  some  dark  varieties  of  pyroxene.  It  oc- 
curs in  greenish-black  splendent  crystals  in  quartz  at  Arendal  in  Nor- 
way. It  has  been  said  to  occur  at  Gouverneur,  N.  Y. 

Breislakite.  In  capillary  crystallizations,  looking  like  reddish  or 
brownish  wool.  It  is  supposed  to  be  near  hornblende.  Occurs  in  lava 
'  at  Vesuvius. 

Forsterite.  Near  chrysolite.  It  occurs  at  Vesuvius,  in  small  color- 
i  less  prismatic  crystals. 

Boltonite.  Massive  with  a  granular  structure  or  in  yellowish  or  blu- 
jish-gray  grains.  Cleavage  in  one  direction.  Luster  vitreous.  Trans- 

What  is  the  usual  color  and  appearance  of  chondrodite  ?     What  is  its 
'hardness?     its  composition?  its  mode  of  occurrence  ?     How  does  it 
i differ  from  tourmaline  and  garnet? 
14 


158  ALUMINA. 

parent  to  translucent.  H=5 — 6.  Gr=2'8 — 2'9.  Composition  :  silica 
46*  1  ;  magnesia  38'1  ;alumina5'7  ;  protoxyd  of  iron  8-6.  Bleaches  and 
becomes  transparent  before  the  blowpipe,  but  does  not  fuse. 

Occurs  disseminated  through  limestone,  at  Bolton,  Mass.,  also  at 
Boxborough  and  Littleton,  Mass.,  and  Ridgefield  and  Reading,  Conn. 

Resembles  chondrodite  in  its  cglor  and  mode  of  occurrence,  but 
differs  in  its  infusibility,  structure  and  color. 

4.     ALUMINA. 
1.     Uncombined. 

SAPPHIRE. 

Rhombohedral.  R  :  Ri=860  8'.  Cleavage  sometimes 
perfect  parallel  with  a.  Usual  in  six-sided 
prisms,  often  with  uneven  surfaces,  and 
sometimes  so  irregular  that  the  form  is 
scarcely  traceable.  Occurs  also  granular. 
Colors  blue,  and  grayish-blue  most  com- 
mon  ;  also  red,  yellow,  brown,  and  nearly 
black  ;  often  bright.  When  polished  on  the  surface  a,  a  star 
of  six  rays,  corresponding  with  the  six-sided  form  of  the 
prism,  is  sometimes  seen  within  the  crystal.  Transparent: 
to  translucent.  H  =  9,  or  next  to  the  diamond.  Exceed- 
ingly tough,  when  compact.  Gr=3*9 — 4' 16. 

Composition  :  pure  alumina.  It  remains  unaltered  before 
the  blowpipe  both  alone  and  with  soda.  Fuses  with  diffi- 
culty with  borax. 

Varieties.  The  name  sapphire  is  sometimes  restricted  in 
common  language  to  clear  crystals  of  bright  colors,  used  as 
gems ;  while  dull,  dingy-colored  crystals  and  masses  are 
called  corundum,  and  the  granular  variety  of  bluish-gray  and] 
blackish  colors  is  called  emery. 

Blue  is  the  true  sapphire  color.  When  of  other  bright 
tints,  it  receives  other  names  ;  as  oriental  ruby,  when  red ; 
oriental  topaz,  when  yellow  ;  oriental  emerald,  when  green  ; 
oriental  amethyst,  when  violet ;  and  adamantine  spar,  when 
hair-brown.  Crystals  with  a  radiate  chatoyant  interior  are! 
often  very  beautiful,  and  are  called  asteria,  or  asteriated 
sapphire. 

What  is  the  usual  form  of  crystals  of  sapphire  ?  What  are  their 
colors  ?  hardness  ?  Of  what  does  sapphire  consist  1  What  are  the  red, 
yellow  and  green  varieties  called  ?  What  the  hair-brown  variety  ? 
What  are  corundum  and  emery  ?  What  is  asteriated  sapphire] 


SAPPHIRE.  159 

Dif.  Distinguished  readily  by  its  hardness,  exceeding  all 
species  except  the  diamond,  and  scratching  quartz  crystals 
with  great  facility. 

Obs.  The  sapphire  is  usually  found  loose  in  the  soil: 
primitive  rocks,  and  especially  gneissoid  mica  slate,  talcose 
rock  and  granular  limestone,  appear  to  be  its  usual  matrix. 
It  is  met  with  in  several  localities  in  the  United  States,  but 
seldom  sufficiently  fine  for  a  gem.  A  blue  variety  occurs  at 
Newton,  N.  J.,  in  crystals  sometimes  several  inches  long  ; 
bluish  and  pink,  at  Warwick,  N.  Y. ;  white,  blue  and  red- 
dish  crystals,  at  Amity,  N.  Y. ;  grayish,  in  large  crystals  in 
Delaware  and  Chester  counties,  Pennsylvania  ;  pale  blue 
crystals  have  been  found  in  boulders  at  West  Farms  and 
Litchfield,  Ct.  It  occurs  also  in  considerable  quantities  in 
North  Carolina ;  also  in  Chester  county,  Georgia,  where  a 
fine  red  sapphire  has  been  obtained. 

The  principal  foreign  localities  are  as  follows  :  blue,  from 
Ceylon ;  the  finest  red  from  the  Capelan  Mountains  in  the 
kingdom  of  Ava,  and  smaller  crystals  from  Saxony,  Bohemia 
and  Auvergne  ;  corundum,  from  the  Carnatic,  on  the  Malabar 
coast,  and  elsewhere  in  the  East  Indies ;  adamantine  spar, 
from  the  Malabar  coast ;  emery,  in  large  boulders  from  near 
Smyrna,  and  also  at  Naxos  and  several  of  the  Grecian 
islands. 

The  name  sapphire  is  from  the  Greek  word  sappheiros, 
the  name  of  a  blue  gem.  It  is  doubted  whether  it  included 
the  sapphire  of  the  present  day. 

Uses.     Next  to  the  diamond,  the  sapphire  in  some  of  its 

|  varieties  is  the  most  costly  of  gems.    The  red  sapphire  is  much 

Imore  highly  esteemed  than  those  of  other  colors.     A  crystal 

weighing  3£  carats,  perfect  in  transparency  and  color,  has 

!  been  valued  at  the  price  of  a  diamond  of  the  same  size.    They 

i  seldom  exceed  half  an  inch  in  their  dimensions.     Two  splen- 

i  did  red  crystals,  as  long  as  the  little  finger  and  about  an  inch 

in  diameter,  are  said  to  be  in  the  possession  of  the  king  of 

:  Arracan. 

Blue  sapphires  occur  of  much  larger  size.  According  to 
j  Allan,  Sir  Abram  Hume  possesses  a  crystal  which  is  three 
',  inches  long  ;  and  in  Mr.  Hope's  collection  of  precious  stones 


How  is  the  species  sapphire  distinguished  ]     In  what  rocks  does  the 
r-np^hire  occur  ?     What  are  some  of  the  American  localities  I  what  are 
i  the  principal  foreign  1     What  is  said  of  the  value  of  sapphires  ? 


160 


ALUMINA. 


there  is  one  crystal  formerly  belonging  to  the  Jardin  de, 
Plantes  of  Paris,  for  which  he  gave  £3000  sterling. 

The  largest  oriental  ruby  known  was  brought  from  China , 
to  Prince  Gargarin,  governor  of  Siberia  ;  it  afterwards  came1 
into  the  possession  of  Prince  Menzikoff,  and  constitutes  now. 
a  jewel  in  the  imperial  crown  of  Russia. 

2.     Combined  with  bases,  forming  Aluminates. 
SPINEL. 


Monometric. 

dodecahedrons. 

1 


In  octahedrons,  more  or  less  modified,  and! 
Figure  1,  is  the  octahedron  with  truncated! 
234 


edges  ;  figure  3,  the  same  with  beveled  edges  ;  figure  2,  the 
dodecahedron.  Occurs  only  in  crystals  ;  cleavage  octahedral, 
but  difficult.  Figure  4  represents  a  twin  crystal. 

Color  red,  passing  into  blue,  green,  yellow,  brown  and 
black.     The  red  shades  often  transparent  and  bright ;  the 
dark    shades    usually    opaque.      Luster    vitreous.      H=8 
Gr=3-5— 3-6. 

Composition  :  of  a  spinel,  from  Haddam,  Ct.,  alumina  75*5, 
magnesia  17*9,  peroxyd  of  iron  4*1,  silica  0*96.  Essentially 
alumina  and  magnesia.  Infusible  alone,  and  with  difficulty 
with  borax. 

Varieties.     The  following  are  the  varieties  of  this  species 
that  have  received  distinct  names  :     The  scarlet  or  bright! 
red   crystals,    spinel   ruby;    the    rose -red,   balas-ruby ;    the 
orange-red,  rubicelle  ;  the  violet,  almandine-ruby ;  the  green, 
chlorospinel ;  while  the  black  varieties  are  called  pleonaste. . 
Pleonaste  crystals  contain  sometimes  16  to  20  per  cent,  of 
oxyd  of  iron. 

Dif.  The  form  of  the  crystals  and  their  hardness  dis- 
tinguish the  species.  Garnet  is  fusible.  Magnetic  iron  ore 

What  is  the  usual  crystalline  form  of  spinel?  What  is  its  hardness? 
What  are  its  colors  ?  Of  what  does  it  essentially  consist  1  Mention  the 
colors  and  names  of  some  of  the  varieties  ? 


SPINEL.  161 

is   attracted  by   the  magnet.     Zircon  has  a  high  specific 
gravity  and  is  not  so  hard. 

Obs.     Occurs  in  granular  limestone ;  also  in  gneiss  and 
|  volcanic  rocks.     At  numerous  places  in  the  adjoining  coun- 
Ities  of  Sussex  in  New  Jersey,  and  Orange  county,  of  various 
i  colors  from  red  to  brown  and  black  ;  especially  at  Franklin, 
Newton  and  Sparta,  in  the  former,  and  in  Warwick,  Amity 
and  Edenville,  in  the  latter.     The  crystals  are  octahedrons, 
and  often  grouped  or  disseminated  singly  in  granular  lime- 
stone.    One   crystal  found  at  Amity  by  Dr.  Heron,  weighs 
49  pounds.     The  limestone  quarries  of  Bolton,  Boxborough, 
Chelmsford  and  Littleton,  Mass.,  afford  a  few  crystals. 

Crystals  of  spinel  are  occasionally  soft,  having  undergone 
a  change  of  composition,  and  approaching  steatite   in  all 
characters  except  form.    They  are  true  pseudomorphs.    They 
I  are  met  with  in  Sussex  and  Orange  counties. 

Uses.  The  fine  colored  spinels  are  much  used  as  gems. 
[  The  red  is  the  common  ruby  of  jewelry,  the  oriental  rubies 
I  being  sapphire.  Crystals  weighing  4  carats  have  been 
•  valued  at  half  the  price  of  a  diamond  of  the  same  size. 

Automolite.  A  variety  of  spinel,  containing  34'8  per  cent,  of  oxyd 
of  zinc.  Color  dark  green  or  black.  H=7'5— 8.  Gr=4"26.  With 
soda  it  forms  at  first  a  dark  scoria,  and  when  fused  again  frith  more 
'soda,  a  ring  of  oxyd  of  zinc  is  deposited  on  the  charcoal.  Infusible 
;  alone,  and  nearly  so  with  borax. 

Occurs  in  granite  at  Haddam  with  beryl,  chrysoberyl,  garnet,  &c.  In 
!  Sweden,  near  Fahlun,  in  talcose  slate. 

Dysluite.  A  variety  of  the  species  spinel,  containing  oxyd  of 
iron  and  zinc.  Color  yellowish  or  grayish -brown.  H=7'5 — 8.  G= 
4'55.  Composition,  alumina  30'5,  oxyd  of  zinc  16'8,  peroxyd  of  iron 
41*9,  protoxyd  of  manganese  7'6,  silica  3,  moisture  0'4.  Becomes  red 
before  the  blowpipe,  but  loses  the  color  on  cooling.  Infusible  alone; 
jwith  borax  affords  a  translucent  bead  of  a  deep  garnet-red  color.  The 
name  dysluite  is  from  the  Greek  dus,  with  difficulty,  and  luo,  to  dis- 
I solve.  From  Sterling,  N.  J.,  with  Franklinite  and  Troostite. 

Hercinite.  A  spinel  consisting  of  alumina  and  protoxyd  of  iron,  with 
only  2~9  per  cent,  of  magnesia. 

3.     Hydrous  combinations  with  Silica. 

HALLO  YLITE. — Hydrous  Silicate  of  Alumina. 
Massive    and    earthy,   resembling   a   compact    steatite. 
'Yields  to  the  nail,  and  may  be  polished  by  it. 

How  is  spinel  distinguished  from  magnetic  iron  ?  from  garnet  ?  from 
zircon?  For  what  are  spinels  used?  What  is  automolite?  What  ia 
the  appearance  of  halloylite  ? 

14* 


162  ALUMINA. 

Color  white  or  bluish.  Adheres  to  the  tongue,  and  small 
pieces  become  transparent  in  water.  Gr=l*8 — 2*1. 

Composition :  silica  39'5,  alumina  34*0,  water  26'5.  DiS% 
solves  in  sulphuric  acid,  yielding  a  jelly.  Becomes  milk- 
white  before  the  blowpipe. 

Obs.  From  Liege  and  Bayonne,  France.  Named  in 
honor  of  the  geologist,  Omalius  d'  Holly. 

NOTE. — There  are  several  other  hydrous  silicates  of  alumina  allied  to 
halloylite,  having  the  following  names  :  Pholerite,  kollyrite,  cimolite, 
bole,  fetlbol, rock  soap,rositc,groppite,  malthacite,  and  smelite.  They 
are  in  general  soft  and  earthy,  often  clay-like,  and  are  distinguished 
from  similar  magnesian  species  by  the  blowpipe  test  for  alumina. 

There  are  also  stalactitic  hydrous  silicates,  found  in  volcanic  and  other 
igneous  rocks,  and  formed  by  the  decomposition  of  feldspar  or  other  in- 
gredients. Such  silico-aluminous  stalactites  are  not  uncommon  in  the 
Pacific  Islands.  They  are  of  mixed  composition,  as  necessarily  results 
from  their  mode  of  origin.  Gibbsite  is  in  some  cases  of  this  character. 
When  containing  an  alkali  they  become  zeolites. 

Allophane.  Reniform  and  massive,  occasionally  with  traces  of  crys- 
tallization ;  sometimes  almost  pulverulent.  Color  pale  blue  ;  sometimes' 
green,  brown  or  yellow.  Luster  vitreous  or  resinous.  Splendent  and 
waxy  internally.  Streak  white.  H=3.  Gr=r85 — 1'90.  Compo-^ 
sition,  alumina  29'2,  silica  21  '9,  water  44'2,  mixed  clay  4- 7.  Becomesi 
opaque,  colorless  and  pulverulent  before  the  blowpipe,  intumesces  a  lit-| 
tie  and  tinges  the  flame  green.  Forms  -a  jelly  with  acids.  In  marl  in 
Thuringia  and  Saxony,  and  in  chalk  at  Beauvais  in  France. 

The  name  allophane  is  from  the  Greek  alias,  other,  and  phaino,  to^ 
appear,  alluding  to  its  changes  of  appearance  before  the  blowpipe. 

Schraetterite,  or  opal  allophane,  resembles  allophane ;  it  consists  of ) 
silica  12'0,  alumina  46'3,  water  36-2,  with  some  iron,  copper  and* 
lime. 

FINITE. 

In  hexagonal  prisms.  Color  gray,  greenish,  brownishJ 
Luster  resinous,  inclining  to  pearly.  Opaque  and  nearly  dullj 
H=2-25.  Gr=2-76— 2-78. 

Composition:  silica  56,  alumina  25'5,  potash  with  some 
soda  8,  peroxyd  of  iron  5'5,  magnesia  with  manganese  3*8, 
water  1*4.  Whitens  before  the  blowpipe,  and  fuses  on  the 
edges  or  not  at  all. 

Obs.  Occurs  in  Auvergne,  in  feldspar  porphyry,  and  in 
granite  in  Saxony  and  Cornwall. 

CHLOROPHYLLITE. 

In  six  and  twelve-sided  prisms,  highly  foliated,  parallel  to 
Of  what  does  halloylite  consist  ? 


ZEOLITES.  163 

I  the  base.     Folia  soft  and  brittle,  of  a  grayish-green  to  dark 
olive-green  color,  and  pearly  luster.     Gr=2*7. 

Composition:  silica  45'2,  alumina  27*6,  magnesia  9'6, 
protoxyd  of  iron  8*2,  protoxyd  of  manganese  4*1,  water  8'6, 
(Jackson.)  Yields  water  before  the  blowpipe  and  becomes 
bluish-gray,  but  fuses  only  on  the  edges. 

Dif.     It  is  distinguished  from  talc  by  affording  water  be-_ 
fore  the  blowpipe,  and  readily  by  its  association  with  iolite, 
and  its  large  hexagonal  forms,  with  brittle  folia. 

Obs.  Occurs  with  iolite  in  granite  at  Haddam,  Ct.,  and  at 
g  Unity,  N.  H.  The  iolite  and  chlorophyllite  are  often  interlami- 
nated,  and  the  latter  appears  to  result  from  the  alteration  of 
',  the  former,  in  which  the  principal  change  is  the  addition  of 
>!  water.  A  variety  from  Brevig,  in  Norway,  has  been  called 
1  esmarkite. 

The  name  chlorophyllite,  given  to  this  species  by  Dr. 
ji  Jackson,  is  derived  from  the  Greek  chloros,  green,  and  phul- 
7o//,  leaf. 

The  following  species,  like  chlorophyllite  in  crystallization,  appear 
I  also  to  have  proceeded  from  the  alteration  of  iolite. 

Fahlunite.  Color  dull  green,  brown  or  black.  H=3.  Gr=2'6 — 
I  2'79.  Contains  13'5  per  cent,  of  water.  From  Fahlun,  Sweden. 

G-igantolite.  Color  greenish  to  dull  steel  gray.  Gr=2.85 — $-88. 
I  From  Tamela,  Finland.  Iberite  is  neargigantolite.  Color  pale  grayish 
I  green.  Gr=2-89.  Hydrous  iolite  of  Bonsdorf,  differs  from  chlorophyllite 
:  in  containing  one  per  cent,  more  of  water. 

Aspasiolite  is  another  hydrous  mineral  allied  to  the  above,  and  found 
I  associated  with  iolite.     It  usually  resembles  a  light  green  serpentine, 
and  occurs  in  six-sided  prisms. 

ZEOLITE    FAMILY. 

NOTE. — The  following  species  from  heulandite  to  chaba- 
zite,  inclusive,  constitute  what  has  been  called  the  zeolite 
family,  so  named  because  the  species  generally  melt  and  intu- 
mesce  before  the  blowpipe,  the  term  being  derived  from  the 
Greek  zeo,  to  boil.  They  consist  essentially  of  silica,  alum- 
ina and  some  alkali,  with  more  or  less  water.  The  most  of 
them  gelatinize  in  acids,  owing  to  the  separation  of  the 
silica  in  a  gelatinous  state. 

They  occur  filling  cavities  in  rocks,  constituting  narrow 
seams,  or  implanted  on  the  surface,  and  rarely  in  imbed- 
ded  crystals ;  and  never  disseminated  through  the  body  of 
a  rock  like  crystals  of  garnet  or  tourmaline.  All  occur 

What  is  the  meaning  of  the  word  zeolite  ?  What  is  the  constitution 
of  the  zeolites  ?  their  mode  of  occurrence  ? 


164  ALUMINA. 

in  amygdaloid,  and  some  of  them  occasionally  in  granite  or 
gneiss.  The  first  four,  heulandite,  laumonite,  apophyllite, 
stilbite,  have  a  strong  pearly  cleavage,  and  do  not  occur  in 
fine  fibrous  crystallizations  ;  when  columnar,  the  structure  is 
thin  lamellar.  Excepting  laumonite,  these  species  dissolve 
in  the  strong  acids,  but  do  not  gelatinize.  The  species 
natrolite,  scolecite,  stellite,  and  thomsonite,  are  often  fibrous, 
and  the  crystallizations  generally  slender.  The  remaining 
species,  harmotome,  analcime,  sodalite,  hauyne,  lapis  lazuli, 
and  chabazite,  occur  in  short  or  stout  glassy  crystals,  and  are 
seldom  fibrous.  To  the  second  division  above  given  might 
be  added  the  species  dysclasite  and  pectolite,  described  under 
Lime.  They  have  a  more  pearly  or  silky  luster  than 
natrolite. 

HEULANDITE. 

M onoclinate.  In  right  rhomboidal  prisms  and  their  modi- 
fications. P  on  M  or  T=90 J.  M  :  T=130°  30'. 
Cleavage  highly  perfect,  parallel  to  P.  Luster  of 
cleavage  face  pearly,  of  other  faces  vitreous.  Color 
white  ;  sometimes  reddish,  gray,  brown.  Transpa- 
rent to  subtranslucent.  Folia  brittle.  H=3%5 — 4. 
Gr=2-2. 

Composition  :  silica  59'1,  alumina  17'9,  lime  7'6, 
water  15.4.  Intumesces  and  fuses,  and  becomes  phospho- 
rescent. Dissolves  in  acid  without  gelatizing. 

Dif.  Distinguished  from  gypsum  by  its  hardness  and  the 
action  of  acids  and  the  blowpipe  ;  from  apophyllite  and  stil- 
bite  by  its  crystals. 

Obs.  Found  in  amygdaloid  ;  occasionally  in  gneiss,  and 
in  some  metalliferous  veins. 

Occurs  at  Bergen  Hill,  N.  J.,  in  trap ;  at  Hadlyme,  Ct., 
and  Chester,  Massachusetts,  on  gneiss ;  near  Baltimore,  on 
a  syenitic  schist ;  at  Peter's-  Point  and  Cape  Blomidon, 
Nova  Scotia,  in  trap. 

The  species  was  named  by  Brooke  in  honor  of  Mr.  Heu- 
land,  of  London.  Lincolnite  is  here  included. 

Srewsterite.  Crystals  right  rhomboidal  prisms,  with  a  perfect 
pearly  cleavage  like  heulandite  ;  but  M  :  T=93°  40'.  H=5— 5. 
Gr=2-l — 2- 5.  From  Argyleshire  and  the  Giant's  Causeway. 


What  is  the  appearance   and  structure  of  heulandite  ?     How  is  it 
distinguished  from  gypsum  1  how  from  apophyllite  and  stilbite  ? 


APOPHYLLITE. 


165 


STILBITE. 

In  right  rectangular  prisms,  more  or  less  modified  ;  cleav- 
age perfect  parallel  with  M.  The  prism  is  usually 
flattened  parallel  with  the  cleavage  face,  (annex- 
ed  figure,)  and  terminates  in  a  pyramid  ;  a  :  a  = 
119  .  Also  in  sheath  like  aggregations  and  thin 
columnar. 

Color  white  ;  sometimes  yellow,  brown  or  red. 
Luster  of  cleavage  face  pearly,  of  other  faces  vitreous.     Sub- 
transparent  to  translucent.     H  =  3-5 — 4.     Gr=2-13 — 2-15. 

Composition :  silica  52'25,  alumina  18-75,  lime  7*4,  soda 
2*4,  water  18*75.  Before  the  blowpipe  fuses  with  intumes- 
cence to  a  colorless  glass.  Does  not  gelatinize  except  after 
long  boiling  in  nitric  acid. 

Dif.  Distinguished  from  gypsum  like  heulandite  ;  and 
from  heulandite  by  its  crystals,  which  are  usually  thin,  elon- 
gated rectangular  prisms,  with  pyramidal  terminations,  often 
uneven  in  surface. 

Obs.  Occurs  mostly  in  amygdaloid  ;  also  on  gneiss  and 
granite. 

It  is  found  sparingly  at  the  Chester  and  Charlestowh  sy- 
enite quarries,  Mass.,  at  Thatchersville  and  Hadlyme,  Ct., 
at  Phillipstown,  N.  Y.,  at  Bergen  Hill,  N.  J.,  in  trap,  in  the 

i  copper  region  of  Lake  Superior,  in  amygdaloid.     In  beauti- 
ful crystallizations  at  Partridge  Island,  Nova  Scotia. 
The  name  stilbite  is  derived  from  the  Greek  stilbe,  luster. 

APOPHYLHTE. 

Dimetric.    In  right  square  prisms  or  octahedrons.    Cleav- 
«  age  parallel  with  the  base  highly  perfect.     Prisms 
•   often  terminate  in  a  sharp  pyramid,  (annexed  fig- 
ure,) a  :  a=104°  2'  and  121°.     Massive  and  fo- 
liated.    Color  white  or  grayish  ;  sometimes  with 
a  shade  of  green,  yellow,  or  red.     Luster  of  P 
pearly  :  of  the  other  faces  vitreous.     Transparent 
!  to  opaque.     H=4'5 — 5.     Gr=2'3 — 2'4. 

Composition:  silica  51*9,  lime   25'2,  potash  5*1,  water 
16-0.     Exfoliates  and  ultimately  fuses  to  a  white  vesicular 
glass.     In   nitric   acid  separates   into  flakes  and  becomes 
i  somewhat  gelatinous  and  subtransparent. 

What  is  the  crystallization  of  stilbite  1  What  are  its  general  char- 
j  acteristics  ?  How  is  it  distinguished  ?  What  is  the  form  and  cleavage 
',  of  crystals  of  apophyllite  ?  What  are  its  other  characters  1 


166  ALUMINA. 

Dif.  The  acute  pyramidal  terminations  of  its  glassy 
crystals  at  once  distinguish  it  from  the  preceding,  as  also  its 
cleavage  across  the  prism. 

The  name  alludes  to  its  exfoliation  before  the  blowpipe. 

Obs.     Found  in  amygdaloidal  trap  and  basalt. 

Occurs  in  fine  crystallizations  at  Peter's  Point  and  Part- 
ridge  Island,  Nova  Scotia,  and  at  Bergen  Hill,  N.  J. 

LAUMONITE. 

Monoclinate.  In  oblique  rhombic  prisms  ;  M  :  M=86° 
15',  P  :  M=66°  30'.  Cleavage  parallel  to  the  acute  lateral 
edge  ;  also  massive,  with  a  radiating  or  divergent  structure. 

Color  white,  passing  into  yellow  or  gray.  Luster  vitre- 
ous, inclining  to  pearly  on  the  cleavage  face.  Transparent 
to  translucent.  H=3%5 — 4.  Gr=2'3.  Becomes  opaque 
on  exposure,  and  readily  crumbles. 

Composition :  silica  48-3,  alumina  22*7,  lime  12*1,  water 
16*0.  Intumesces  and  fuses  to  a  white  frothy  mass.  Ge- 
latinizes with  nitric  or  muriatic  acid,  but  is  not  affected  by 
sulphuric  unless  heated. 

Dif.  The  alteration  this  species  undergoes  on  exposure 
to  the  air,  at  once  distinguishes  it.  This" result  may  be  pre- 
vented with  cabinet  specimens,  by  dipping  them  into  a  solu- 
tion of  gum  arable. 

Obs.  Found  in  amygdaloid  and  also  in  gneiss,  porphyry, 
and  clay  slate.  Peter's  Point,  Nova  Scotia,  is  a  fine  locality 
of  this  species.  Occurs  also  at  Phipsburg,  Me. ;  Charles- 
town  syenite  quarries,  Mass. ;  Bergen  Hill,  N.  J. ;  in  the 
amygdaloid  of  the  copper  region,  Lake  Superior. 

Leonhardite  resembles  laumonite  ;  it  contains  silica  55,  alumina  24- 1, 
lime  10-5,  water  and  loss  12-30. 

NATROLITE. 

Trimetric.  In  right  rhombic  prisms,  usually  slender  and 
terminated  by  a  short  pyramid  ;  M  :  M=91°  10  ;  e  : 
e=143>  14',  M  :  e=116  37'.  Cleavage  perfect 
parallel  with  M.  Also  in  globular,  stellated,  and  di- 
vergent groups,  consisting  of  delicate  acicular  fibers, 
the  fibers  often  terminating  in  acicular  prismatic 
crystals. 

Color  white,  or  inclining  to  yellow,  gray,  or  red. 

How  is  apophyllite  distinguished  ?  What  are  the  characters  of  lau- 
monite ?  What  takes  place  when  it  is  exposed  to  the  air  ?  What  is 
the  crystallization  of  natrolite  ?  mention  other  characters. 


THOMSONITE.  167 

Luster  vitreous.  Transparent  to  translucent.  H=4*5 — 5*5. 
Brittle.  Gr=2-14— 2-23. 

Composition  :  silica  48*0,  alumina  26'5,  soda  16*2,  water 
9*3.  Becomes  opaque  before  the  blowpipe  and  fuses  to  a 
glassy  globule.  Forms  a  thick  jelly  in  the  acids,  after  heat- 
ing as  well  as  before. 

Dif.  Distinguished  from  scolecite  by  its  action  before  the 
blowpipe. 

Obs.  Found  in  amygdaloidal  trap,  basalt  and  volcanic 
rocks.  The  name  natrolite  is  from  natron,  soda. 

Occurs  iii  the  trap  of  Nova  Scotia  and  Bergen  Hill,  N.  J. 

Scolecite  resembles  natrolite,  and  differs  in  containing  lime  in  place 
of  soda.  The  luster  is  vitreous  or  a  little  pearly.  Before  the  blowpipe 
it  curls  up  like  a  worm  (whence  the  name  from  the  Greek  skolex  a 
worm)  and  then  melts.  From  Staffa,  Iceland,  Finland,  Hindostan. 

Poohnahlite  is  a  related  species,  from  Poohnah,  Hindostan.  M  :  M  = 
92°  20'. 

Jlesole  is  another  related  species,  occurring  usually  in  implanted  glo- 
bules, having  a  flat  columnar  or  lamellar  radiated  structure,  with  a 
pearly  or  silky  luster.  Gr=2'35 — 2'4.  Fuses  easily  before  the  blow- 
pipe and  gelatinizes  readily  with  acids.  From  the  Faroe  islands  and 
Greenland.  Harringtonite  from  the  north  of  Ireland,  and  JBrevicite 
from  Brevig,  Norway,  appear  to  be  identical  with  mesole. 

Natrolite,  scolecite,  mesole,  and  some  other  zeolites,  together  corres- 
>ond  to  the  old  species  mesotype. 

THOMSOXITE. 

Trimetric.  In  right  rectangular  prisms.  Usually  in 
nasses,  having  a  radiated  structure  within,  and  consisting  of 
ong  fibers  or  acicular  crystals  ;  also  amorphous. 

Color  snow-white.  Luster  vitreous,  inclining  to  pearly. 
Transparent  to  translucent.  H=4'75.  Brittle.  Gr=2'3 
— 2-4. 

Composition  :  silica  38-3,  alumina  30-7,  lime  13-5,  soda 
1'5,  water  13'1.  Inturnesces  and  becomes  ooaque  ;  but  the 
edges  merely  are  rounded  at  a  high  heat.  When  pulverized, 
t  gelatinizes  with  nitric  or  muriatic  acids. 

Dif.  Distinguished  from  natrolite  and  other  zeolites  by 
ts  difficult  fusibility. 

Obs.  Occurs  in  amygdaloid,  near  Kilpatrick,  Scotland  ; 
n  lavas  at  Vesuvius  ;  in  clinkstone  in  Bohemia.  Also  at  Pe- 
er's Point,  Nova  Scotia,  in  trap. 

The  species  was  named  in  honor  of  Dr.  Thomas  Thorn- 
son,  of  Glasgow. 

The  species  comptonite  and  mowenite  are  identical  with  thomsonite. 


168 


ALUMINA. 


HARMOTOME. 

Trimetric.  In  modified  rectangular  prisms ;  and  very 
commonly  twin  crystals  similar  to  the  annexed 
figure. 

Color  white  ;  sometimes  grayish,  yellowish, 
or  brownish.  Subtransparent  to  translucent. 
Luster  vitreous.  H=4* — 4-5.  Brittle.  Gr== 
2-39— -2-45. 

Composition :  silica  46-6,  alumina  16-8,  ba- 
ryta 20-3,  lime  0'3,  potash  I'O,  water  15-0. 
Fuses  without  intumescence  to  a  clear  globule.  Phospho- 
resces with  a  yellow  light  when  heated.  Scarcely  attacked 
by  the  acids  unless  they  are  heated. 

Dif.  Its  twin  crystals,  when  distinct,  cannot  be  mistaken 
for  any  other  species  except  phillipsite.  It  is  much  more 
fusible  than  glassy  feldspar  or  scapolite  ;  it  does  not  gelati- 
nize in  cold  acids  like  thomsonite. 

Obs.  Occurs  in  amygdaloid,  gneiss,  and  metalliferous 
veins.  Fine  crystallizations  are  found  at  Strontian  in  Ar- 
gyleshire,  Andreasberg  in  the  Hartz,  and  Kongsberg  in 
Norway. 

The  name  harmotome  is  from  the  Greek  harmos  a  joint, 
and  temno  to  cleave. 

Phillipsite.  Near  harmotome  in  its  cruciform  crystals  and  other 
characters  ;  but  differing  in  containing  lime  in  place  of  baryta.  It  dif- 
fers also  in  gelatinizing  with  acids  and  in  fusing  with  some  intumes- 
cence. It  also  occurs  in  sheaf-like  aggregations  and  in  radiated  crys- 
tallizations. From  the  Giant's  Causeway,  Capo  di  Bove,  and  Vesuvius. 
Gismondine  and  zeagonite,  from  the  last  two  localities  mentioned,  are 
identical  with  Phillipsite. 

ANALCIME. 

Monometric.     Occurs  usually  in  trapezohedrons,  (fig.  1.) 
also  fig.  2  ;   cleavage   cubic  and  2 

only  in  traces. 

Often  colorless  and  transparent, 
also  milk-white,  grayish  and  red- 
dish-white, and  sometimes  opaque. 
The  appearance  sometimes  seen 
in  polarized  light  is  shown  in  figure  96,  page  61. 
Luster  vitreous.  H  =  5 — 5'5.  Gr=2'07 — 2'28. 

What  is  the  common  form  of  harmotome  ?  what  its  color  and  ap- 
pearance ?  What  are  its  distinguishing  characters?  What  is  the  form 
of  crystals  of  analcime  1  the  color  and  other  characters  1 


CHABAZITE.  169 

Composition:  silica  55*1,  alumina  23,  soda  13*5,  water 
8'3.  Fuses  before  the  blowpipe  on  charcoal  wrthont  intu- 
mescence to  a  clear  glassy  globule.  Gelatinizes  in  muriatic 
acid. 

Dif.  Characterized  by  its  crystallization,  without  cleav- 
age. Distinguished  from  quartz  and  leucite  by  its  inferior 
hardness  ;  from  calc  spar  by  its  fusibility,  and  by  not  effer- 
vescing with  acids  ;  from  chabazite  and  its  varieties  by  fu- 
sing without  intumescence  to  a  glassy  globule,  and  by  the 
crystalline  form. 

Obs.     Found  in  amygdaloid  and  lavas  ;  also  in  gneiss. 

Occurs  in  fine  crystallizations  in  Nova  Scotia  ;  also  at 
Bergen  Hill,  N.  J. ;  Perry,  Me.  ;  and  in  the  amygdaloid  of 
the  copper  region,  Lake  Superior.  The  Faroe  Ids.,  Iceland, 
Vicentine,  the  Hartz,  Sicily,  and  Vesuvius  are  some  of  the 
foreign  localities. 

The  name  analcime  is  from  the  Greek  analJcis,  weak,  al- 
luding to  its  weak  electric  power  when  heated  or  nibbed. 

CHABAZITE. 

Rhombohedral.     Often  in  rhombohedrons,   much  resem- 
bling cubes.     (Fig.  1.)     R  :  R  =  94°  46'.     Cleavage  paral- 
12  3 


lei  to  the  primary  faces.  Also  in  complex  modifications  of 
this  form,  and  double  six-sided  pyramids  or  short  six-sided 
prisms  terminating  in  truncated  pyramids.  (Fig.  2.)  Also 
in  compound  crystals,  (fig.  3.)  Never  massive  or  fibrous. 

Color  white,  also  yellowish   and  red.     Luster  vitreous.  ' 
Transparent  to  translucent.     H  =  4 — 4-5.     Gr=2'06 — 2-17. 

Composition :  silic?  49'4,  alumina  19*3,  lime  8*7,  potash 
2-5,  water  21-1. 

This  species  includes  gmelinite,  occurring  in  small  glassy 
crystals  of  the  form  in  figure  2  ;  also  levyne,  occurring  in 
compound  crystals  (fig.  3 ;)  also  ledererite,  which  has  the  form 

• — 

Mention  some  of  the   distinctive  characters  of  analcime.     What  is 
said  of  the  crystallization  of  chabazite?  mention  other  characters. 
13 


170  ALUMINA. 

of  gmelinite,  but  appears  to  differ  in  containing  just  one  third  1 
the  proportion  of  water ;  also  phacolite,  occurring  in  small  i 
glassy  crystals  having  the  form  of  double  six-sided  pyramids. 
The  acadiolite  is  a  red  variety  from  Nova  Scotia.     Herschel- 
ite  is  another  variety  in  small  hexagonal  tables. 

The  varieties  intumesce  and  whiten  before  the  blowpipe, 
Gmelinite  forms  a  jelly  with  acids. 

Dif.    The  nearly  cubical  form  often  presented  by  the  crystals  • 
of  chabazite  is  a  striking  character.     It  is  distinguished  from 
analcime  as  stated  under  that  species ;  from  calc  spar  by  its 
hardness  and  action  with  acids ;  from  fluor  spar  by  its  form 
and  cleavage,  and  its  showing  no  phosphorescence. 

Obs.  Found  in  trap,  gneiss,  and  syenite.  Chabazite  is 
met  with  in  the  trap  of  the  Connecticut  valley,  but  in  poor 
specimens  ;  also  at  Hadlyme,  and  Stonington,  Ct.,  at  Charles- 
town,  Mass.,  Bergen  Hill,  N.  J.,  Piermont,  N.  Y.  Nova 
Scotia  affords  common  chabazite  and  also  the  ledererite.  The 
Faroe  Islands,  Iceland,  and  Giant's  Causeway  are  some  of 
the  foreign  localities.  Gmelinite  comes  from  the  Vicentine  ; 
also  the  county  of  Antrim,  Ireland  ;  levyne  from  Glenarm, 
Scotland  ;  also  Iceland,  Faroe,  &c. 

Haydenite.  Resembles  chabazite  in  the  appearance  of  its  crystals, 
but  is  described  as  having  an  oblique  rhombic  prism  ;  P  :  M=96°  5f, 
M  :  M=98°  22*.  Occurs  with  heulandite  at  Jones's  Falls,  near  Balti- 
more. 

PREHNITE. 

Primary  form  aright  rhombic  prism;  M  :  M  =  99°  56'. 
Cleavage,  basal.  Usually  in  six-sided  prisms,  round- 
ed so  as  to  be  barrel- shaped,  and  composed  of  a 
series  of  united  plates ;  also  in  thin  rhombic  or 
hexagonal  plates.  Often  reniform  and  botryoidal ; 
texture  compact. 

Color  light  green  to  colorless.  Luster  vitreous, 
except  the  face  P,  which  is  somewhat  pearly.  Subtranspa- 
rent  to  translucent.  H  =  6 — 6-5.  Gr  =  2*8 — 2-96. 

Composition :  silica  43'0,  alumina  23*25,  lime  26*0,  pro- 
toxyds  of  iron  and  manganese  2 '25,  water  4*0.  On  char- 
coal before  the  blowpipe  froths  and  melts  to  a  slag  of  a  light 
green  color.  Dissolves  slowly  in  muriatic  acid  without  ge- 
latinizing, leaving  a  flaky  residue. 

How  is  chabazite  distinguished  from  calc  spar?  how  from  fluorspar? 
What  is  the  usual  form  and  structure  of  prehnite?  What  is  ita 
color  ?  4uster  I  hardness  ? 


PREHNITE.  171 

Dif.  Distinguished  from  beryl,  green  quartz,  and  chalce- 
dony by  fusing  before  the  blowpipe,  and  from  the  zeolites  by 
its  superior  hardness.  The  ordinary  broken  appearance  of 
its  crystals  is  quite  characteristic. 

Obs.     Found  in  trap,  gneiss,  and  granite. 

Occurs  in  the  trap  of  Farmington,  and  Woodbury,  Ct.; 
West  Springfield,  Mass.,  and  Patterson  and  Bergen  Hill,  N. 
J. ;  in  gneiss  at  Bellows  Falls,  Vt. ;  in  syenite  at  Charlestown, 
Mass. ;  and  very  abundant,  forming  a  large  vein,  in  the  cop- 
per region  of  Lake  Superior,  three  miles  south  of  Cat  har- 
bor, and  elsewhere. 

The  Fassa  valley  in  the  Tyrol,  St.  Crystophe  in  Dauphi- 
ny,  and  the  Salisbury  Crag,  near  Edinburgh,  are  some  of  the 
foreign  localities. 

Uses.  Prehnite  receives  a  handsome  polish  and  is  some- 
times used  for  inlaid  work.  In  China  it  is  polished  for  orna- 
ments, and  large  slabs  have  been  cut  from  masses  brought 
from  there. 

Epistilbite.     A  hydrous  silicate  of  alumina  and  lime.     Occurs  in 

i  thin  rhombic  prisms,  of  a  white  color,  with  a  perfect  pearly  cleavage 

like  stilbite.     H=4  45.     Gr=2'25.     Before   the  blowpipe  froths   and 

forms  a  vesicular  enamel.     Does  not  gelatinize.     From  Iceland  and 

Hindostan,  and  sparingly  at  Bergen  Hill,  N.  J. 

Stellite.  In  fibrous  stellar  groups  like  mesole  ;  luster  silky  and  shi- 
i  ning.  H=3  25.  Gr=2'6l2.  Fuses  to  a  white  enamel.  Gelatinizes 
,  with  muriatic  acid.  From  Kilsyth,  Scotland. 

Antrimolite.     A  stalactitic  zeolite,  from  Antrim,  Ireland. 
Edingtonite.     In  small  right  square  prisms,  with  lateral  cleavage. 
!  Kearly  colorless  ;  luster  vitreous.     H=4 — 4'5.     Gr=2  7— 2- 75.     Oc- 
curs with  thomsonite  at  Dumbartonshire. 

Carpholitc.  In  minute  radiated  and  stellate  tufts  of  a  straw  yellow 
'  color,  and  silky  luster.  From  the  tin  mines  of  Schlackenwald,  Aus- 
,  tria ,  with  fluor. 

Diphanite.     In  six-sided  prisms  with  a  distinct  basal  cleavage  ;  vit- 
reous luster,  transparent.     H=5 — 5'5.     Gr=3 — 3.1.     A  silicate   of 
.  alumina  and  lime,  and  near  prehnite.     From  the  Ural,  with  emerald. 

Hydrous   anthophyUite.   In  divergent  fibers  having  a  silky  luster. 
>  H=2'5.     Gr=2'91.     Color  white,  greenish-yellow  or  bluish.     Occurs 
in  a  talcose  rock  at  Fishkill,  N.  Y.,  and  also  above  New  York  city. 

Faujasile.     A  hydrous  silicate  of  alumina,  lime  and  soda.     Crystals 
square  octahedrons.     A  :  A=lll°  30'  and  105°  30'     Scratches  glass. 
I  Occurs  with  augite,  at  Kaiserstuhl. 

Glottahte.    ~A  hydrous  silicate  of  alumina  and  lime,  said  to  be  mon- 
ometric  in  crystallization.     H=3  5.     Gr=2'18.     Color  white.    Luster 
I  vitreous.     Translucent.     From  Scotland. 

Where  does  prehnite  occur  ?  How  is  it  distinguished  from  the  zeo- 
L  Htes  and  quartz  ?  What  are  it?  uses  ? 


172  ALUMINA. 

Zeuxite.  A  hydrous  silicate  of  alumina  and  iron,  in  small  brown 
prismatic  crystals,  of  a  vitreous  luster.  H=4'25.  Gr=3'05.  From 
Cornwall,  in  the  Huel  Unity  Mine. 

Datuouritf.  Occurs  in  lamellar  pearly  crystals,  a  little  harder  than 
talc.  Gr=2'7 — 2-82.  It  is  a  hydrous  silicate  of  alumina  and  potash. 
Reported  from  Leiperville,  Penn.,  and  Chesterfield,  Mass. 

Chloritoid.  A  coarsely  foliated  mineral,  folia  beet,  brittle  ;  color 
greenish-black.  H=5'5 — Gr=3  55.  Infusible  before  the  blowpipe, 
but  becomes  finally  black  and  magnetic.  From  the  Ural. 

Masonite.  Near  chlorhoid  ;  coarsely  foliated  or  tabular  ;  color  dark 
gray;  luster  nearly*  pearly;  folia  brittle  and  often  curved.  H=6. 
Gr=3'45.  Fuses  with  difficulty  on  the  edges.  From  the  vicinity  of 
Natic  village,  Rhode  Island. 


4,     Anhydrous  combinations  with  Silica. 

SILLIMANITE. 

tn  long,  slender  rhombic  prisms,  often  much  flattened, 
penetrating  the  gangue.  M  :  M  =  11(P — 98°.  A  brilliant 
and  easy  cleavage,  parallel  to  the  longer  diagonal.  Also  in 
masses,  consisting  of  aggregated  crystals  or  fibers. 

Color  hair-brown  or  grayish-brown.  Luster  vitreous,  in- 
clining to  pearly.  Translucent  crystals  break  easily.  H= 
7—7-5.  Gr=3-2— 3-3. 

Composition  :  silica  37 '70,  alumina  62 -75,  oxyd  of  iron 
2'28,  (Norton.)  Identical  therefore  with  kyanite.  Infu-, 
sible  alone  and  with  borax. 

Dif.  Distinguished  from  tremolite  and  the  varieties  gen- 
erally of  hornblende  by  its  brilliant  diagonal  cleavage,  and 
its  infusibility ;  from  kyanite  by  its  brilliant  cleavage,  and  a 
rhombic,  instead  of  flat-bladed  crystallization. 

*  Obs.  Found  in  gneiss  at  Chester,  Ct.,  and  the  Falls  of 
the  Yantic,  near  Norwich,  Ct.  The  long,  slender  prisms 
penetrate  the  gangue  in  every  direction.  Also  in  Yorktown, 
Westchester  county,  N.  Y. 

This  species  was  named  by  Bowen  in  honor  of  Prof.  B. 
SilKman  of  Yale  College. 

Bacholzite.  This  species  is  near  Sillimanite  in  its  acicular  crystal- 
lizations and  physical  characters.  Composition,  silica  46'4,  alumina 
52-' 9,  (Thomson.)  A  specimen  from  Chester,  Penn.,  gave  Erdmann, 
silica  40*1,  alumina  58'9,  protoxyd  of  manganese.  From  Fassa,  Tyrol  \ 
also  from  Chester,  Penn.  ;  Munroe,  Orange  county,  N.  Y.  ;  Worcester, 
Mass. ;  and  Humphrey sville,  Conn. 

What  is  the  crystallization  and  appearance  of  Sillimanite  ?  What  is 
its  hardness!  How  is  it  distingui .hod  from  tremolite  and  kyanite? 


KYAXITE.  173 

The  analyses  of  bucholzite,  if  accurate,  indicate  that  different  species 
are  included  under  that  name.  The  American  mineral  so  called,  is 
evidently  identical  with  Sillimanite. 

KYANITE. 

Triclinate.  Usually  in  long  thin-bladed  crystals  aggre- 
gated together,  or  penetrating  the  gangue.  The  annexed 
figure  is  a  portion  of  one  of  these  crystals.  Crystals 
sometimes  short  and  stout.  Lateral  cleavage,  dis- 
tinct. Sometimes  fine  fibrous. 

Color  usually  light  blue,  sometimes  white,  or  a 
blue  center  with  a  white  margin ;  sometimes  gray, 
green,  or  even  black.  Luster  of  flat  face  a  little 
pearly.  H=5 — 7.  Rather  brittle,  but  less  so  than 
Sillimanite.  Gr=3'6 — 3.7. 


Composition  :  silica  37*0,  alumina  62*5.  Unaltered  alone 
before  the  blowpipe.  With  borax  forms  slowly  a  transparent 
colorless  glass. 

Dif.  Distinguished  by  its  infusibility  from  varieties  of 
the  hornblende  family.  The  short  crystals  have  some  re- 
semblance to  staurotide,  but  their  sides  and  terminations  are 
usually  irregular  ;  they  differ  also  in  their  cleavage  and 
luster. 

Obs.  Found  in  gneiss  and  mica  slate,  and  often  accom- 
panied by  garnet  and  staurotide. 

Occurs  in  long-bladed  crystallizations  at  Chesterfield  and 
Worthington,  Mass. ;  at  Litchfield  and  Washington,  Conn.  ; 
near  Philadelphia ;  near  Wilmington,  Delaware ;  and  in 
Buckingham  and  Spotsylvania  counties,  Va.  Short  crystals 
(sometimes  called  improperly  jibrolite)  occur  in  gneiss  at 
Bellows  Falls,  Vt.,  and  at  Westfield  and  Lancaster,  Mass. 

In  Europe,  transparent  crystals  are  met  with  at  St.  Goth- 
ard  in  Switzerland,  and  in  Styria,  Carinthia,  and  Bohemia. 
Villa  Rica  in  South  America,  affords  fine  specimens. 

The  name  kyanite  is  from  the  Greek  kuanos,  sky-blue. 
It  is  also  called  sappar,  a  corruption  of  sapphire  ;  also  dis- 
ihene,  and  when  white,  rhcetizite. 

Uses.  Kyanite  is  sometimes  used  as  a  gem,  and  has 
some  resemblance  to  sapphire. 

Warthite.  Resembles  kyanite,  but  gives  off  water  before  the  blow- 
pipe. It  may  be  an  altered  kyanite.  From  St.  Petersburg. 

Describe  kyanite  ?  What  is  the  origin  of  the  name  1  For  what  is 
it  used? 

lo* 


174 


ALUMINA. 


M 


ANDALUSITE. 

Trimetric.  In  right  rhombic  prisms.  M  :  M=91°  33'. 
Cleavage  lateral,  distinct ;  also  massive  and 
indistinctly  coarse  columnar,  but  never  fine 
fibrous. 

Colors  gray  and  flesh-red.  Luster  vitreous, 
or  inclining  to  pearly.  Translucent  to  opaque. 
Tough.  H=7-5.  Gr=3-l— -3-32. 

Composition :  silica  36*5,  alumina  60*5,  per- 
oxyd  of  iron  4'0.  [nfusible.  With  borax  fuses  with  ex- 
treme difficulty. 

Varieties.  Chiastolite  and  made  are  names  given  to 
crystals  of  andalusite  which  show  a  tesselated  or 
cruciform  structure  when  broken  across  and  pol- 
ished. The  annexed  figure  represents  one  from 
Lancaster,  Mass.  The  structure  is  owing  to  im- 
purities, (usually  the  material  of  the  gangue,)  disseminated 
by  the  powers  of  crystallization  in  a  regular  manner  along 
the  sides,  edges  and  diagonals  of  the  crystal.  Their  hard- 
ness is  sometimes  as  low  as  3.  The  same  structure  has 
been  observed  by  Dr.  Jackson  in  staurotide  crystals. 

Dif.     Distinguished  from  pyroxene,  scapolite,  spodymene 
and  feldspar,  by  its  infusibility,  hardness  and  form. 
Obs.     Found  in  granite  and  gneiss. 

Westford,  Mass.  ;  Litchfield  and  Washington,  Ct. :  Ban- 
gor,  Me. ;  Chester,  Penn.,  are  some  of  its  American  locali- 
ties. Chiastolite  occurs  at  Sterling  and  Lancaster,  Mass., 
and  near  Bellows  Falls,  Vermont.  This  species  was  first 
found  at  Andalusia  in  Spain. 

STAUROTIDE. 

Trimetric.     In  right  rhombic  and  six-sided  prisms.     M  : 
1        M=129°  20'.     Cleavage   imperfect.  2 

P  :  a=124°  38',  M  :  e=115°  20'. 
Figure  2  is  a  common  cruciform 
crystal,  (consisting  of  two  prisms 
crossing  one  another.)  Never  in 
massive  forms  or  slender  crystalli- 
zations. 


What  is  the  appearance  of  andalusite  ?  What  is  chiastolite  or  made  1 
How  is  andalusite  distinguished  from  pyroxene  and  spodumene  '?  What 
crystalline  forms  are  presented  by  staurotide  ]  Is  it  ever  found  massive  1 


LEUCITE.  175 

Color  dark  brown  or  black.  Luster  vitreous,  inclining  to 
resinous  ;  sometimes  bright,  but  often  dull.  Translucent  to 
opaque.  H=7— 7*5.  Gr=3'65— 3'73. 

Composition:  silica  37*5,  alumina  41-0,  protoxyd  of  iron 
18*25,  protoxyd  of  manganese  and  magnesia  1*0.  Before 
the  blowpipe  it  darkens,  but  does  not  fuse. 

Dif.  Distinguished  from  tourmaline  and  garnet  by  its 
infusibility  and  form. 

Obs.  Found  in  mica  slate  and  gneiss,  in  imbedded 
crystals. 

Very  abundant  through  the  mica  slate  of  New  England. 
Franconia,  Vt.  ;  Windham,  Me. ;  Lisbon,  N.  H.  ;  Chester* 
field,  Mass. ;  Bolton  and  Tolland,  Ct. ;  on  the  Wichichon, 
eight  miles  from  Philadelphia,  and  near  New  York  city,  are 
some  of  the  localities,  St.  Gothard  in  Switzerland,  and  the 
Greiner  mountain,  Tyrol,  are  noted  foreign  localities. 

The  name  staurotide  is  from  the  Greek  stauros,  a  cross* 

LEUCITE, 

Occurs  only  under  the  form  of  the  trapezohedron,  as  in  the 
annexed  figure.  Cleavage  imperfect.  Usually 
in  dull  glassy  crystals,  of  a  grayish  color ;  some- 
times opaque-white,  disseminated  through  lava. 
Translucent  to  opaque.  H=5*5 — 6.  Brittle. 
Gr=2-48— 2-49. 

Composition :  silica  54,  alumina  23,  potash  22,  (Klaproth.) 
Infusible  except  with  borax  or  carbonate  of  lime,  and  then 
with  difficulty  to  a  clear  globule.  A  fine  blue  color,  with 
cobalt  solution. 

Dif.  Distinguished  from  analcime  by  its  hardness  and 
infusibility. 

Obs.  In  lavas,  especially  those  of  Italy.  Abundant  at 
Vesuvius.  Crystals  from  a  pin's  head  to  an  inch  in  di- 
ameter. 

The  name  leucite  is  from  the  Greek  leukos,  white. 

Saccharite  resembles  a  granular  feldspar,  of  a  white  or  greenish- white 
color,  but  has  the  constitution  of  leucite.  Infusible  alone,  and  with 
great  difficulty  with  soda.  From  Silesia. 


What  are  the  colors  and  hardness  of  staurotide  ?  What  is  ita  con- 
stitution ?  What  is  its  mode  of  occurrence  1  How  is  it  distinguished 
from  tourmaline  ?  Describe  the  forms  and  appearance  of  leucite.  How 
does  it  differ  from  analcime  ? 


176  ALUMINA  r 


FELDSPAR** 

Monoclinate.  In  modified  oblique  rhombic  prisms.  T  ', 
T=118D  49',  P  :  T==67J  15';  T  -,  e=120°  40'.  Usually 
in  thick  prisms,  often  rectangular,  (fig.  2,) 
and  also  in  modified  tables,  (fig.  1.) 
Cleavage  perfect  parallel  with  e,  the 
shorter  diagonal ;  also  distinct  parallel 
to  P.  Also  massive,  with  a  granular 
structure,  or  coarse  lamellar.  Colors  light ; 
white,  gray,  and  flesh-red  common  ;  also  greenish  and  bluish 
white  and  green.  Luster  vitreous  ;  sometimes  a  little  pearly 
on  the  face  of  perfect  cleavage.  Transparent  to  subtranslu- 
cent.  H=6.  Gr= 2*3.9— 2-62. 

Composition:  silica  64*20,  alumina  18*40,  potash  16*95, 
Fuses  only  on  the  edges.  With  borax  forms  slowly  a  trans- 
parent glass.  Not  acted  upon  by  the  acids* 

Varieties.  Common  feldspar  includes  the  common  sub- 
translucent  varieties  ;  adularia,  the  white  or  colorless  sub- 
transparent  specimens.  The  name  is  derived  from  Adula, 
one  of  the  highest  peaks  of  St.  Gothard.  Glassy  feldspar 
and  ice-spar  include  transparent  vitreous  crystals,  found  in. 
lavas.  Some  crystals  called  by  these  names  belong  to  the 
species  anorthite,  or  ryacolite. 

Moonstone  is  an  opalescent  variety  of  adularia,  having 
when  polished  peculiar  pearly  reflections.  Sunstone  is  simi- 
lar ;  but  contains  minute  scales  of  mica.  Aventurine  feld- 
spar often  owes  its  iridescence  to  minute  crystals  of  specular 
or  titanic  iron. 

Dif.  Distinguished  from  scapolite  by  its  more  difficult 
fusibility,  and  by  a  slight  tendency  to  a  fibrous  appearance 
in  the  cleavage  surface  of  the  latter,  especially  in  massive 
varieties  ;*from  spodumene  by  its  blowpipe  characters. 

Obs.  Feldspar  is  one  of  the  constituents  of  granite, 
gneiss,  mica  slate,  porphyry  and  basalt,  and  often  occurs  in 
these  rocks  in  crystals.  St.  Lawrence  county,  N.  Y.,  affords 
fine  crystals  ;  also  Orange  county,  N.  Y.  ;  Haddam  and 

What  is  the  crystallization  and  appearance  of  feldspar  1  What  is  its 
hardness  1  what  its  composition  ?  Mention  the  principal  varieties,  with 
their  peculiarities  ]  In  what  rocks  is  feldspar  an  ingredient  ? 

t  The  following  species,  from  feldspar  to  nepheline  inclusive,  form  a 
natural  group  called  the  feldspar  family. 


FELDSPAR*  177 

Middlelown,  Coim.  ;  South  Royalston  and  Barre,  Mass., 
besides  numerous  other  localities.  Green  feldspar  occurs  at 
Mount  Desert,  Me.  ;  an  aventurine  feldspar  at  Leyperville, 
Penn, ;  Adularia  at  Haddam  and  Norwich,  Conn.,  and  Par- 
sonsfield,  Me.  A  fetid  feldspar  (sometimes  called  necronite) 
is  found  at  Rogers'  Rock,  Essex  county ;  at  Thomson's 
quarry,  near  196th  street  New  York  city,  and  21  miles  from 
Baltimore.  Carlsbad  and  Elbogen  in  Bohemia,  Baveno  in 
Piedmont,  St.  Gothard,  Arendal  in  Norway,  Land's  End,  and 
the  Moarne  mountains,  Irelaad,  are  some  of  the  more  inter- 
esting foreign  localities. 

The  name  feldspar  is  from  the  German  word/e/J,  mean- 
ing field, 

Uses.  Feldspar  is  used  extensively  in  the  manufacture  of 
Porcelain.  Moonstone  and  Sunst&ne  are  often  set  in  jewelry. 
They  are  pofished  with  a  rounded  surface,  and  look  some- 
what like  cat's-eye,  but  are  much  softer. 

Kaolin,  This  name  is  applied  to  the  clay  that  results 
from  the  decomposition  of  feldspar.  It  is  the  material  used 
for  making  porcelain  or  china  ware.  The  change  the  feld- 
*par  undergoes  in  producing  kaolin  consists  principally  in  a 
removal  of  the  alkali,  potash,  with  part  of  the  silica  and  the 
addition  of  water.  Composition  of  a  specimen  from  Schnee- 
foerg,  silica  43-6,  alumina  37*7,  peroxyd  of  iron  1*5,  water 
12'6,  (Berthier.)  It  occurs  in  extensive  beds  in  granite  re- 
gions, where  it  has  been  derived  from  the  decomposition  of 
this  rock.  A  granite  containing  talc  seems  to  be  the  most 
common  source  of  it.  See  farther,  tfee  chapter  on  Rocks. 

ALBITE. 

TricRnate,      In    modified    oblique    rhomboidal    prisms. 
M  :  T=117°  53,  P  :  T=115°  5  ;  P  :  M=93° 
50  .     The  crystals  are  usually  more  or  less  thick 
and  tabular.     Also  massive,  with  a  granular  or 
lamellar  structure.     Laminae  brittle. 

Color  white  ;  occasionally  Hght  tints  of  bluish 
white,  grayish,  reddish  and  greenish.  Luster 
vitreous  to  pearly,  and  sometimes  a  bluish  opalescence  is 
exhibited.  Transparent  to  ssbtranslucent,  H=6.  Gr= 
2-6—2-7. 


What  are  the  nses  of  feldspar  ?     Wbat  is  kaolin,  and  for  what  is  k 
oaed  ?     What  is  the  crystaJ lization  and  appearance  of  albite  2 


178  ALUMINA- 

Composition:  silica  68'5,  alumina  19'3,  peroxyd  of  iron 
and  manganese  0'3,  lime  0*7,  soda  9-1.  Acts  like  feldspar 
before  the  blowpipe,  but  tinges  the  ftame  yellow. 

Cleavelandite  is  a  lamellar  variety  occurring  in  wedge- 
shaped  masses  at  the  Chesterfield  albite  vein,  Mass. 

Dif.  Albite  differs  from  feldspar  in  containing  a  large- 
proportion  of  soda.  It  may  generally  be  distinguished  when 
associated  with  that  species  by  its  uniform*  white  color ;  also 
by  the  form  of  the  crystals,  which  are  more  oblique  and  ir- 
regular, often  tabular,  with  two  of  the  edges  very  acute  ;  also* 
by  the  yellow  tinge  given  the  blowpipe  Same. 

Obs.  Albite  like  feldspar  is  a  constituent  of  many  rocks, 
replacing  feldspar.  Albite  granite  is  commonly  lighter 
colored  than  feldspar  granite,  arising  from  the  izsual  white- 
ness of  the  albite.  Fine  crystals  occur  at  Middletown  and 
Haddam,  Conn.,  at  Goshen,  Mass.,,  and  Granville,  N.  Y. 

The  name  albite  is  from  the  Latin  albus,  white. 

Myacolite.  Resembles  albite,  occurring  in  transparent  glassy  crystals, 
H=6.  Gr=2'5 — 2'7.  Crystals  oblique  rhombic,  nearly  like  those  of 
feldspar.  M  :  M=119°  21'.  Contains  10  per  cent.,  of  soda,  and  like 
albite  tinges  the  flame  before  the  blowpipe  yellow.  It  fuses  rather  more 
easily  than  feldspar.  From  Mount  So-mma  and'  the  EifeL 

Anorthite.  Near  albite.  The  primary  is  an  oblique  rhwnboidaj 
prism,  P  :  T=110°  57'  T  :  T=120°  30'.  Its  crystals  are  glassy  and 
tabular  in  form.  H=G.  Gr=2'6— 2'8.  Differs  from  albite  in  noS 
tinging  the  blowpipe  flame  deep  yellow,  nor  affording  a  dear  glass  with 
soda.  From  Mount  Somrna,  near  Naples. 

Loxoclase.  Has  the  form  of  feldspar  very  nearly,  but  is  distinguished 
by  a  cleavage  parallel  with  the  longer  diagonal,  T  :  T=119Q  30'. 
H=6— 6-5.  Gr=2-6— 2-62.  Contains  8-8  per  cent,  of  soda  and  3 -a 
of  potash.  From  Hammond,  N.  Y.,  where  it  occurs  with  pyroxene,, 
graphite  and  calc  spar. 

LABRADORITR. 

Triclinate.  P  :  M=9&°  28-',  P  :  T=114°  4S',  M  :  T~ 
119°  16'.  Cleavage  parallel  with  P,  nearly  per- 
fect ;  M  distinct.  Usually  in  cleavable  massive 
forms. 

Color  dark  gray,  brown,  or  greerash  brown  ; 
and  usually  a  series  of  bright  chatoyant  colors 
from  internal  reflections,,  especially  blue  and  green,  with 
more  or  less  of  yellow,  red  and  pearl-gray.  Translucent, 


Hew  does  albite  differ  from  feldspar  ?    What  is  clea-velandite  1  WkuJ 
is  peculiar  in.  die  colors  of  labradorite  I    Mention  oJker  characters. 


LABfiADORITE.  179 

fobtranslucent.  Luster  of  principal  cleavage  face  pearly ; 
other  faces  vitreous.  H=6.  Gr=2'69 — 2-76. 

Composition  :  silica  55*75,  alumina  26.5,  peroxyd  of  iron, 
1-25,  lime  li-0,  soda  4'0,  Water  0'5.  Like  feldspar  before 
the  blowpipe,  but  fuses  with  a  little  less  difficulty  to  a  color- 
less glass.  Entirely  dissolved  by  muriatic  acid, 

Dif.  Differs  from  feldspar  and  albite  in  containing  a 
large  percentage  of  lime,  and  it  is  farther  distinguished  by 
dissolving  in  muriatic  acid,  and  generally  by  its  chatoyant 
reflections. 

Obs.  A  constituent  of  some  granites,  and  was  originally 
from  Labrador.  It  is  abundant  in  Essex  county,  N.  Y.,  at 
Moriah,  Westport  and  Lewis.. 

Uses.  Labradorite  receives  a  fine  polish,  and  owing  to 
the  chatoyant  reflections  of  rich  and  delicate  colors,  the  speci- 
mens are  often  highly  beautiful.  It  is  sometimes  used  in 
jewelry. 

Glaucolite,  Considered  by  Frankenheim  identical  with  Labradorite. 
Color  lavender-blue,  passing  into  green.  From  near  Lake  Baikal  in 
Siberia. 

Oligoclasc.  A  feldspar-like  mineral,  with  a  distinct  cleavage,  nearly 
white  color,  of  imperfectly  vitreous  to  somewhat  greasy  luster.  H=6. 
Gr=2-64— 2  67.  Composition,  silica  €3^5,  alumina  23-1,  lime  24, 
potash  2"2,  soda  9'4,  magnesia  08.  Fuses  with  difficulty,  and  not  at- 
tacked by  acids.  Occurs  at  Stockholm  in  granite,  and  at  Arendal, 
Norway,  and  elsewhere,  in  granular  limestone. 

Lime-oligoclase  is  an  allied  mineral  from  Iceland, 

Couzeranite,  another  allied  species  from  the  Pyrenees,  of  a  gray  or 
greenish  gray  color.  Composition  near  that  of  Labradorite. 

Latrobite.  Resembles  some  reddish  scapolites,  but  occurs  in  oblique 
rhomboidal  prisms,  like  the  feldspars;  P  :  M=91°  9',  P  :  T=98°  30% 
M  :  T=93°  30'.  Also  in  cleavable  masses.  H=6.  Gr=2'7— 2'8, 
Composition,  silica  41'8,  alumina  32  8,  lime  9'8,  oxyd  of  manganese 
with  magnesia  5'8,  potash  6'6,  water,  2'0.  Fuses  with  some  intu- 
mescence. From  Labrador  in  granite. 

Arnphodelite  is  united  with  the  species  anorthite- 

NEPHELIXE. 

In  hexagonal  prisms.  Also  massive;  some- 
times thin  columnar. 

Color  white,  or  gray,  yellowish,  greenish,  bluish- 
red.  Luster  vitreous  or  greasy.  Transparent  to 
opaque.  H=5'5-^6.  Gr=2'4— 2'65. 

Varieties  and  Composition.     Nepheline  includes 

How  does  it  differ  from  feldspar  and  albite  ?  For  what  is  it  used  I 
"What  is  the  form  of  crystals  of  nepheline  ?  Mention  its  colors  and  luster. 


180  ALUMINA* 

glassy  crystals  from  Vesuvius,  which  become  eloodecf  in 
nitric  acid.  The  name  is  from  the  Greek  nephele,  a  cloud. 

ElcBolite  (from  elaion,  oil)  includes  the  dingy  translucent 
or  subtranslucent  cleavable  masses  having  a  strong  greasy 
luster.  Crystals  from  Greenland  have  been  called  giescckite* 
Cancrinite  is  a  bluish  variety. 

Nepheline  contains  silica  43'4,  ahtmina  33'S,  peroxydl 
of  iron  1*5,  lime  0*9,  soda  13*4,  potash  7*1,  water  1'4. 
Rounded  on  the  edges  before  the  blowpipe  :  some  varieties 
fuse  readily.  In  nitric  acid,  fragments  become  clouded  and 
gelatinize. 

Dif.  Distinguished  from  scapolite  and  feldspar  by  the? 
greasy  luster  when  massive,  and  forming  a  jelly  with  acids  j 
from  apatite  by  the  same  characters,  and  also  its  hardness, 

Obs.  Nepheline  occurs  at  Vesuvius  and  near  Rome,  irt 
lava.  ElcBolite  is  obtained  at  Brevig  and  other  places  in 
Norway ;  also  in  Siberia.  It  is  also  found  in  the  Ozark 
mountains  in  Arkansas,  and  at  Litchfield  in  Maine, 

SCAPOLITE. 

Dimetric.  In  modified  square  prisms,  often  terminating  in 
pyramids;  a  :  a  =  136°  7'.  Cleavage  rather 
indistinct  parallel  with  M  and  e.  Also  mas- 
sive, sublamellar  or  subfibrous. 

Colors  light ;  white,  pale  blue,  green  or  red. 
Streak  uncolored.  Transparent  to  nearly 
opaque.  Luster  usually  a  little  pearly.  H= 
5—6.  Gr  =  2-6— 2-75, 

Composition :  silica  41*25,  alumina  33*6, 
lime  20*4,  protoxyd  of  manganese  0*5,  water  3*2.  Before 
the  blowpipe  it  fuses  slowly  with  intumescence.  With  borax 
dissolves  with  effervescence  to  a  transparent  glass. 

Dif.  Its  square  prisms  and  the  angle  of  the  pyramid  at 
summit  are  characteristic.  In  cleavable  masses  it  resembles 
feldspar,  but  there  is  a  slight  fibrous  appearance  often  dis- 
tinguished on  the  cleavage  surface  of  scapolite,  which  is 
peculiar.  It  is  more  fusible  than  feldspar,  and  has  higher 
specific  gravity.  Spodumene  has  a  much  higher  specific 
gravity,  and  differs  in  its  action  before  the  blowpipe.  Tabu- 

What  hav6  specimens  with  a  greasy  luster  been  called  ?  What  is  the 
effect  of  nitric  acid  1  What  is  the  usual  form  of  scapolite  crystals? 
What  are  its  colors  and  hardness  1  What  is  its  composition  1  How 
does  it  differ  from  feldspar  and  tabular  spar  ? 


SPODUMENE,  181 

lar  spar  is  more  fibrous  in  the  appearance  of  the  surface, 
and  is  less  hard ;  it  is  also  phosphorescent,  and  gelatinizes 
with  acids, 

Obs.  Found  mostly  in  the  older  crystalline  rocks,  and 
also  in  some  volcanic  rocks.  It  is  especially  common  in 
granular  limestone.  Fine  crystals  occur  at  Gouverneur,  N. 
Y.,  and  at  Two  ponds  and  Amity,  N.  Y. ;  at  Bolton, 
Boxborough  and  Littleton,  Mass. ;  at  Franklin  and  Newton, 
N.  J.  It  occurs  massive  at  Marlboro',  Vt. ;  Westfield,  Mass. ; 
Monroe,  Ct.  Foreign  localities  are  at  Arendal,  Norway ; 
Warmland,  Sweden  ;  Pargas  in  Finland,  and  also  at  Vesu- 
vius, whence  comes  the  small  crystals  called  meionite. 

Nnttallite,  Wernerite,  and  Meionite  are  varieties  of  this  species. 

Dipyre  from  the  Pyrenees,  occurring  in  four  or  eight-sided  prisms,  has 
also  been  considered  one  of  its  varieties.  It  however  contains  silica 
55-5,  alumina  24'8,  lime  9' 6,  with  9'4  per  cent,  of  soda,  and  is  more 
allied  in  composition  to  the  feldspars.  Sp.  gr.=2'65.  Occurs  with  talc 
and  chlorite. 

Geklenite.  Crystals  square  prisms  like  meionite :  color  gray ;  nearly 
opaque.  H=5'5 — 6.  Gr=2'9 — 3'1.  Composition,  silica  29' 6,  alum- 
ina 24-8,  lime  35  3,  protoxyd  of  iron  6'6,  water  33.  Infusible.  With 
borax  fuses  with  difficulty.  Gelatinizes  in  muriatic  acid.  From  the 
Fassa  valley,  Tyrol. 

Ifumboldtilite,  Crystals  as  above.  Cleavage  basal,  distinct.  Color 
brown  or  yellow ;  luster  vitreous.  H=5.  Gr=2>9— 3'2.  Composi- 
tion, silica  44'0,  alumina  ITS,  lime  32'0,  magnesia  6-l,  protoxyd  of 
iron  2-3,  soda  4'3,  potash  0'4.  Gelatinizes  with  nitric  acid.  From 
Vesuvius  in  lava.  Somermllite  and  mellilite  are  here  included. 

SPODUMENE. 

In  cleavable  masses,  yielding  rhombic  prisms  of  93°. 
Surface  of  cleavage  pearly.  Color  grayish  or  greenish. 
Translucent  to  subtranslucent.  H  =  6-5 — 7.  Gr=3'l — 
3-19. 

Composition :  silica  65*3,  alumina  25*3,  lithia  6-8,  oxyd  of 
iron  2*8.  Intumesces  before  the  blowpipe,  and  fuses  to 
a  transparent  glass.  In  fine  powder  mixed  with  bisulphate 
of  potash  and  fluor,  and  fused  on  platinum  foil,  it  tinges  the 
flame  red,  owing  to  the  lithia  contained. 

Dif.  Resembles  somewhat,  feldspar  and  scapolite,  but 
has  a  higher  specific  gravity  and  a  more  pearly  luster,  and 
affords  rhombic  prisms  by  cleavage. 

In  what  rocks  does  it  occur  ?  Mention  the  characters  of  spodumene. 
How  much  lithia  does  it  contain  ?  How  does  it  differ  from  feldspar  and 
ecapolite  ? 

16 


J82  ALUMINA. 

Obs.  Occurs  in  granite  at  Goshen  ;  also  at  Chesterfield, 
Chester  and  Sterling,  Mass.  ;  at  Windham,  Me. ;  at  Brook- 
field,  Ct.  It  is  found  at  Uton  in  Sweden,  Sterzing  in  the 
Tyrol,  and  at  Killiney  bay,  near  Dublin. 

Triphane  is  another  common  name  of  this  mineral. 

Uses.  This  mineral  is  remarkable  for  the  litk-ia  it  con- 
tains, and  has  been  used  for  obtaining  this  rare  earth. 

PETALITE. 

In  imperfectly  cleavable  masses,  affording  a  prism  of  95*. 
Color  white  or  gray,  or  with  pale  reddish  or  greenish  shades. 
Lusler  vitreous  to  subpearly.  Translucent.  H— 6 — 6'5. 
Gr—2-4— 2-45. 

Composition  :  silica  79*2,  alumina  17*2,  lithia  5'8.  Phos- 
phoresces when  gently  heated.  Fuses  with  difficulty  on  the 
edges.  Gives  the  reaction  of  lithia  like  spodumene. 

Dif.  Its  lithia  reaction  allies  it  to  spodumene ;  b«at 
it  differs  from  that  mineral  in  luster,  specific  guavity,  and 
greater  fusibility. 

Weissite.  A  somewhat  pearly,  massive  mineral,  of  an  ash-gray  or 
brownish  color,  consisting  of  silica  53' 7,  alumina  21 '7,  magnesia  9-0, 
potash  4*1,  sodaO'7,  protoxyds  of  iron,  manganese  and  zinc  2'1.  From 
Fahlun.  Glaucophane  affords  nearly  the  same  composition.  Occurs 
in  cleavable  masses  of  a  dull  bluish  color,  and  in  thin  prisms.  Trans- 
lucent. Gr=l-08.  H=5-5.  Fuses  easily.  Contains  silica  56-5, 
alumina  12'2,  protoxyd  of  iron  IO9,  protoxyd  of  manganese  05,  mag- 
nesia 8-0,  lime  2-2,  soda  9'3.  From  the  Island  of  Syra. 

Wichtine  is  a  black  mineral  rectangularly  cleavable  in  two  direc- 
tions. Contains  silica  56'3,  alumina  13  3,  protoxyd  of  iron  13'0,  p«r- 
oxyd  of  iron  4'0,  soda  3'5,  lim«  G'O,  magnesia  3'0.  From  Wichty  in 
Finland. 

EPIDOTE. 

Monoclinate.     In  right  rhomboidal  prisms  more   or  less 
modified,   often  with  six  or  more   sides.     M  :  T=115C 
T  :  e=128°  19' ;  a  :  a=109° 
27';  e  :  a=125°  16' 

Cleavage  parallel  to  M  ;  less 
distinct  parallel  to  T. — Also 
massive  granular  and  of  a  co- 
lumnar structure. 

Describe  petalite.  What  is  the  proportion  of  lithia  in  its  constitution  ? 
How  does  it  differ  from  spodumene  ?  Where  does  it  occur  1  What  is 
the  form  of  epidote  ? 


EPIDOTE,  183 

Color  yellowish-green  (pistachio-green)  and  ash  or  hair 
brown.  Streak  uncoloredl  Translucent  to  opaque.  Lus- 
ter vitreous,  a  little  pearly  on  M  ;  often  brilliant  on  the  faces 
of  crystals.  Brittle.  H=6— 7.  Gr=3'25 — 3-46. 

Varieties  and  Composition.  There  are  three  prominent 
varieties  of  this  species ;  one  of  a  yellowish -green  color, 
another  called  zoisite,  of  a  grayish-brown  or  hair-brown  ;  a 
third  of  dark  reddish  shades,  which  contains  14  per  cent,  of 
oxyd  of  manganese,  and  is  called  Manganesian  epidote* 
Thulite  is  another  red  variety,  of  -paler  <color. 

The  yellowish  -green  epidote  is  sometimes  called  Pistatite. 
The  mineral  Bucklandite  is  an  iron-epidote. 

The  green  epidote  consists  of  silica  37*0,  alumina  26'o*, 
It  me  20 '0,  protoxyd  of  iron  13 '0,  protoxyd  of  manganese  0.6, 
water  T8. 

Zoisite  consists  of  silica  40*2,  alumina  30'3,  lime  22*5, 
peroxyd  of  iron  4*5,  water  2.0.  Before  the  blowpipe,  epidote 
and  zoisite  fuse  OR  the  edges  and  swell  up,  but  do  not  liquefy. 
The  manganesian  epidote  and  thulite  fuse  readily  to  a  black 
.glass. 

Dif.  The  peculiar  yelk>\vish-green  color  of  ordinary  ep- 
idote distinguishes  it  at  once.  The  prisms  of  zoisite  are 
often  longitudinally  striated  or  fluted,  and  they  have  not  the 
form  or  brittleness  of  tremolite. 

Obs.  Occurs  in  crystalline  rocks,  and  also  in  some  sedi- 
mentary rocks  that  have  been  heated  by  the  passage  of  dykes 
;of  trap  or  basalt.  Splendid  crystals,  six  inches  long,  and 
>!with  brilliant  faces  and  rich  color,  have  been  obtained  at 
Haddam,  Ct.  Crystallized  specimens  are  also  found  at  Fran- 
*conia,  N.  H.,  HacRyme,  Chester,  Newbury  and  Athol,  Mass^ 
^near  Unity  and  Monroe,  N,  Y.,  Franklin  and  Warwick,  N. 
.J.  Zoiske  in  columnar  masses  is  found  at  Willsboro  and 
Montpelier,  Vt,  at  Chester,  Goshen,  Chesterfield,  and  else- 
where in  Massachusetts  ;  at  Milford,  Ct. 

The  name  epidote  was  derived  by  Hauy  from  the  Greek 
fpididomi,  to  increase,  in  allusion  to  the  fact  that  the  base  of 
:the  primary  is  frequently  much  enlarged  in  some  of  the  se- 
•condary  forms.  Zoisite  was  named  in  compliment  to  its  dis- 
coverer, Baron  von  Zois. 


What  are  the  colors  and  other  characters  of  epidote  ?  What  is  the  col- 
ter of  the  variety  zoisite  ?  What  is  the  composition  of  epidote  ?  what 
zse  iie  disUnguishJBg  characters  1 


184  ALFMI1NA. 


IDOCRASE. 

Dimetric.  In  square  prisms  usually  modified.  P  :  a— 
142°  53';  a  :  a=129°  28',  a  :  e=l21°  07. 
Cleavage  not  very  distinct  parallel  with  M.  Also 
found  massive  granular  and  subcolumnar. 

Color  brown  ;  sometimes  passing  into  green. 
In  some  varieties  the  color  is  oil-green  in  the  direc- 
tion of  the  axis  and  yellowish-green  at  right  angles 
with  it.  Streak  uncolored.  Subtransparent  to  nearly  opaque. 
H=6-5.  Gr=3-33— 3.4. 

Composition :  silica  37*4,  alumina  23*5,  protoxyd  of  iron 
4*0,  lime  29*7,  magnesia  and  protoxyd  of  manganese  5*2. 
Before  the  blowpipe  fuses  with  effervescence  to  a  yellow 
translucent  globule. 

Dif.  Resembles  some  brown  varieties  of  garnet,  tourma- 
line and  epidote,  but  besides  its  difference  of  crystallization, 
it  is  much  more  fusible. 

Obs.  Idocrase  was  first  found  in  the  lavas  of  Vesuvius, 
and  hence  called  Vesuvian.  It  has  since  been  obtained  in 
Piedmont,  near  Christiania,  Norway,  in  Siberia,  also  in  the 
Fassa  valley.  Specimens  of  a  brown  color  from  Eger,  Bo- 
hernia,  have  been  called  egeran.  Cyprinc  includes  blue 
crystals  from  Tellemarken,  Norway ;  supposed  to  be  colored 
by  copper. 

In  the  United  States,  idocrase  occurs  in  fine  crystals  at 
Phipsburg  and  Rumfbrd,  Parsonsfield  and  Poland,  Me. ; 
Newton,  N.  J. ;  Amity,  N.  Y.,  and  sparingly  at  Worcester, 
Mass.  The  xanthite  of  Amity  is  nothing  but  idocrase. 

The  name  idocrase  is  from  the  Greek  eido,  to  see,  and, 
JcrasiS}  mixture ;  because  its  crystalline  forms  have  much  re- 
semblance to  those  of  other  species* 

Uses.  This  mineral  is  of  little  value  except  as  a  minera- 
logical  curiosity.  It  is  sometimes  cut  as  a  gem  for  rings. 

GARNET. 

Monometric.  Common  m  dodecahedrons,  (fig.  I,}  also  in 
trapezohedrons,  (fig.  2,)  and  both  forms  are  sometimes  vari- 
ously modified.  Cleavage  parallel  to  the  faces  of  the  dode- 

What  is  the  crystallization  of  idocrase  ?  its  color,  harcfoess,  and  Ins- .; 
ter?  its  composition  1     How  does  it  differ  from  garnet  and  tourmaline1? 
What  is  the  usual  form  of  garnet  1 


CARPET.  185 

cahedron  rathef  distinct.     Also  found  massive  granular,  and 
coarse  lamellar. 


Color  deep  red,   prevalent;   also  brown,    black,  green, 
1234 


white.  Transparent  to  opaque.  Luster  vitreous.  Brittle. 
H=6-5— 7-5.  Gr=3-5— 4-3. 

Varieties  and  Composition.  Garnet  is  a  compound  of  three 
or  four  silicates,  the  silicates  of  alumina,  lime,  iron,  and 
manganese,  and  the  varieties  of  color  arise  from  their  vari- 
ous combinations.  Oxyd  of  chrome  is  sometimes  present,  pro- 
ducing an  emerald-green  variety, 

Precious  garnet  or  almandine  is  a  clear  deep  red  variety, 
and  is  used  much  in  jewelry.  A  specimen  from  New  York 
afforded  Wachtmeister,  silica  42'5,  alumina  19*15,  protoxyd 
of  iron  33'6,  protoxyd  of  manganese  5*5. 

Common  garnet  has  a  brownish  red  color,  and  is  imper- 
fectly translucent  or  opaque. 

Cinnamon  stone,  called  also  essonite,  is  of  a  light  cinna- 
mon-yellow color  and  high  luster.  It  differs  from  the  pre- 
ceding principally  in  containing  but  5  or  6  per  cent,  of  iron 
and  30  to  33  percent,  of  lime.  Topazolite  is  another  yellow 
variety,  approaching  topaz  in  color,  and  presenting  the  form 
in  figure  3. 

Melanite  (from  the  Greek  melas,  black)  is  a  black  garnet, 
containing  15  to  25  per  cent,  of  the  oxyds  of  iron  and  man- 
ganese. Pyrendite  is  another  name  for  a  black  variety  from 
France. 

Manganesian  garnet  has  a  deep  red  color,  and  is  usually 
quite  brittle.  A  Haddam  specimen  afforded  Seybert,  silica 
35-8,  alumina  18' 1,  protoxyd  of  iron  14*9,  protoxyd  of  man- 
ganese 31'0. 

Grossularite  occurs  in  greenish  trapezohedrons  ;  and  con- 
tains 30  to  34  per  cent,  of  lime  with  but  little  iron. 

Ouvarovite  is  a  chrome  garnet,  containing  22-5  per  cent,  of 
oxyd  of  chromium,  and  having  the  rich  color  of  the  emerald. 

What  is  the  color  and  hardness  of  garnet?  of  what  does  it  consist  1 
what  is  precious  garnet  1  What  is  cinnamon  stone  1  What  is  ouvaro- 
vitel 


186  ALUMINA. 

Colophonite  (from  the  Greek  kolophoniar  a  resin)  is  a 
Coarse  granular  variety,  usually  presenting  iridescent  hues 
and  a  resinous  luster. 

Aplome  is  a  deep  brown  garnet,  sometimes  inclining  to 
orange.  It  presents  the  form  in  figure  4,  and  has  a  cleavage 
parallel  to  the  shorter  diagonal  of  the  faces.  For  this  rea- 
son it  has  been  separated  from  the  species  garnet,  and  a  cube 
is  considered  its  primary  form. 

The  different  varieties  fuse  with  more  or  less  difficulty  to 
a  dark  vitreous  globule. 

Dif.  The  vitreous  luster  of  fractured  garnet,  without  a 
prismatic  structure  even  in  traces,  and  its  usual  dodecahedral 
forms,  are  easy  characters  for  distinguishing  it.  Staurotide 
differs  in  being  infusible  ;  tourmaline  has  less  specific  grav- 
ity ;  idocrase  fuses  much  more  readily. 

Obs.  Garnet  occurs  abundantly  in  mica  slate,  hornblende 
slate,  and  gneiss,  and  somewhat  less  frequently  in  granite 
and  granular  limestone  ;  sometimes  in  serpentine  and  lava. 

The  best  precious  garnets  are  from  Ceylon  and  Greenland ; 
cinnamon  stone  comes  from  Ceylon  and  Sweden ;  grossularite 
occurs  in  the  Wilui  river,  Siberia,  and  at  Tellemarken  in  Nor- 
way ;  green  garnets  are  found  at  Swartzenberg,  Saxony ; 
melanite,  in  the  Vesuvian  lavas  ;  ouvarovife,  at  Bissersk  in 
Russia ;  topazolite,  at  Mussa,  Piedmont ;  aplome,  in  Siberia, 
on  the  Lena,  and  at  Swartzenberg. 

In  the  United  States,  precious  garnets,  of  small  size,  occur 
at  Hanover,  N.  H. ;  and  a  clear  and  deep  red  variety,  some- 
times called  pyrope,  comes  from  Green's  creek,  Delaware 
county,  Penn.  Dodecahedrons,  of  a  dark  red  color,  occur  at 
Haverhill,  N.  H. ;  some  1|  inches  through  ;  also  at  New 
Fane,  Vt.,  still  larger  ;  also  Lyme,  Conn. ;  at  Unity,  Bruns- 
wick, Streaked  Mountain,  and  elsewhere,  Maine  ;  at  Monroe, 
Conn. ;  Bedford,  Chesterfield,  Barre,  Brookfield,  and  Brim- 
field,  Mass. ;  Dover,  Dutchess  county,  Roger's  rock,  Crown 
Point,  Essex  county,  Franklin,  N.  J.  Cinnamon  colored 
crystals  occur  at  Carlisle,  Mass.,  transparent,  and  also  at 
Boxborough  ;  with  idocrase  at  Parsonsfield,  Phippsburg  and 
Rumford,  Me. ;  at  Amherst,  N.  H.  ;  at  Amity,  N.  Y.,  and 
Franklin,  N.  J., ;  at  Dixon's  quarry,  seven  miles  from  Wil- 
mington, Del.,  in  fine  trapezohedral  crystals.  Melanite  is 
found  at  Franklin,  N.  J.,  and  Germantown,  Penn.  Coloph- 

What  is  colophonite  ?  What  is  aplome  ?  How  is  garnet  distinguished  ? 


TOURMALINE.  187 

onite  is  abundant  at  Willsborough  and  Lewis,  Essex  county, 
N.  Y.  ;  it  occurs  also  at  North  Madison,  Conn. 

The  garnet  is  the  carbuncle  of  the  ancients.  The  ala- 
bandic  carbuncles  of  Pliny  were  so  called  because  cut  and 
polished  at  Alabanda,  and  hence  the  name  Almandine  now 
in  use.  The  garnet  is  also  supposed  to  have  been  the  hya- 
cinth of  the  ancients. 

Uses.  The  clear  deep  red  garnets  make  a  rich  gem, 
and  are  much  used.  Those  of  Pegu  are  most  highly  valued. 
They  are  cut  quite  thin,  on  account  of  their  depth  of  color. 
An  octagonal  garnet,  measuring  85  lines  by  6£  has  sold  for 
near  8700.  The  cinnamon  stone  is  also  employed  for  the 
same  purpose.  Pulverized  garnet  is  sometimes  employed  as 
a  substitute  for  emeiy.  When  abundant,  as  in  some  parts  of 
Germany,  garnet  is  used  as  a  flux  to  some  iron  ores. 

Pliny  describes  vessels,  of  the  capacity  of  a  pint,  form- 
ed from  large  carbuncles,  "  devoid  of  luster  and  transparen- 
cy, and  of  a  dingy  color,"  which  probably  were  large  gar- 
nets. 

Pyrope  or  Bohemian  garnet.  Occurs  usually  in  rounded  grains,  re- 
sembling a  rich  garnet,  but  the  primary  form  is  supposed  to  be  the  cube. 
Cleavage  none.  H=7  5.  Gr=3  69 — 38.  Composition :  silica  43'0, 
alumina  22  3,  oxyd  of  chromium  T8,  magnesia  18'5,  protoxyd  of  iron 
8'7,  lime  5'7  ;  and,  according  to  Apjohn,  there  are  also  3  per  cent,  of 
yttria.  From  Bohemia,  in  trap  tufa. 

Helvin,  a  wax  yellow  garnet-like  mineral,  occurring  in  tetrahedral 
crystals.  From  Saxony  and  Norway. 

TOURM  ALINE. 

Rhombohedral.     Usual  in  prisms  terminating  in  a  low 
pyramid.     R    :  R  =  133° 
26.     R   :  e  =  113°    17'; 

:a  =  141D40  ;  e  :  e=  [j 
155°  9  .     The  crystals  are 
hemihedrally  modified,  or 
have     unlike      secondary 
planes  at  the  two  extrem- 
ities, as  shown  in  figure 
3.     They  are  commonly  long,  and  often  there  are  but  three 
prismatic   sides,  which  are  convex  and  strongly  furrowed. 

How  is  garnet  distinguished  ?  What  are  its  uses?  What  is  said  of 
the  ancient  carbuncle  ?  What  is  pyrope  ?  What  are  the  usual  forms  and 
appearance  of  tourmaline  ? 


188  ALUMINA. 

Occurs  also  compact  massive,  and  coarse  columnar,  the  col- 
umns sometimes  radiating  or  divergent  from  a  center. 

Color  black,  blue-black,  and  dark  brown,  common  ;  alsc 
bright  and  pale  red,  grass -green,  cinnamon-brown,  yellow, 
gray,  and  white.  Sometimes  red  within  and  green  external- 
ly, or  one  color  at  one  extremity  and  another  at  the  other. 
Transparent ;  usually  translucent  to  nearly  opaque.  Luster 
vitreous,  inclining  to  resinous  on  a  surface  of  fracture. 
Streak  uncolored.  Brittle ;  the  crystals  often  fractured 
across  and  breaking  very  easily.  H=7'8.  Gr  =  3 — 3*1. 
Electrically  polar  when  heated,  (page  62.)  . 

Varieties  and  Composition.  Tourmalines  of  different  col- 
ors have  been  designated  by  different  names,  as  follows  :— 

Rubellite  is  red  tourmaline. 

Indicolite  is  blue  and  bluish-blacJc  tourmaline. 

Schorl,  formerly  included  the  common  black  tourmaline, 
but  the  name  is  not  now  used. 

A  black  variety  afforded,  on  analysis,  silica  33*0,  alumina 
38-2,  lime  0'8,  pi-otoxyd  of  iron,  23-8,  soda  3-2,  boracic  acid 
1*9. 

A  red  variety  from  Siberia,  silica  39'4,  alumina  44*0,  pot- 
ash 1*3,  boracic  acid  4*2,  lithia  2'5,  peroxyd  of  manganese 
5*0.  The  presence  of  boracic  acid  is  the  most  remarkable 
point  in  the  constitution  of  this  mineral.  It  is  also  observed 
that  lithia  is  sometimes  present ;  over  4  per  cent,  have  been 
obtained  from  a  green  tourmaline  from  Uton,  Sweden. 

Before  the  blowpipe  the  dark  varieties  intumesce,  and  fuse 
with  difficulty ;  the  red  and  light-green  only  become  milk- 
white  and  a  little  slaggy  on  the  surface. 

Dif.  The  black  and  the  dark  varieties  generally,  are 
readily  distinguished  by  the  form  and  luster  and  absence  of 
distinct  cleavage,  together  with  their  difficult  fusibility.  The 
black  when  fractured  often  appear  a  little  like  a  black  resin. 
The  brown  variety  resembles  zoisite,  though  very  dis- 
tinct in  crystallization.  The  light  brown  looks  like  garnet 
or  idocrase,  but  is  more  infusible.  The  red,  green,  and  yel- 
low varieties  are  distinguished  from  any  species  they  resem- 
ble, by  the  crystalline  form,  the  prism  of  tourmaline  always 
having  3,  6,  9,  or  12  prismatic  sides,  (or  some  multiple  of 


What  is  the  color  and  hardness  of  tourmaline  ?  what  has  been  called 
schorl?  What  is  rubellite?  What  are  the  distinctive  characters  of 
tourmaline  ? 


TOURMALINE.  189 

3.)  The  electric  polarity  of  the  crystals,  when  heated,  is 
another  remarkable  character  of  this  mineral. 

Obs.  Tourmalines  are  common  in  granite,  gneiss,  niica 
slate,  chlorite  slate,  steatite,  and  granular  limestone.  They 
usually  occur  penetrating  the  gangue.  The  black  crystals 
are  often  highly  polished  and  at  times  a  foot  in  length,  though 
perhaps  of  no  larger  dimensions  than  a  pipe-stem,  or  even 
more  slender.  This  mineral  has  also  been  observed  in 
sandstones  near  basaltic  or  trap  dikes. 

Red  and  green  tourmalines,  over  an  inch  in  diameter  and 
transparent,  have  been  obtained  at  Paris,  Me.,  besides  pink 
and  blue  crystals.  These  several  varieties  occur  also,  of  less 
beauty,  at  Chesterfield  and  Goshen,  Mass.  Good  black  tour- 
malines are  found  at  Norwich,  New  Braintree,  and  Carlisle, 
Mass. ;  Alsted,  Acworth,  and  Saddleback  Mountain,  N.  H. ; 
Haddam,  Conn. ;  Saratoga  and  Edenville,  N.  Y. ;  Franklin 
and  Newton,  N.  J.  * 

Dark  brown  tourmalines  are  obtained  at  Orford,  N.  H. ;  in 
thin  black  crystals  in  mica  at  Grafton,  N.  H. ;  Monroe,  Ct. ; 
Gouverneur  and  Amity,  N.  Y.  ;  Franklin  and  Newton,  N. 
J.  A  fine  cinnamon  brown  variety  occurs  at  Kingsbridge, 
Amity,  and  also  south  in  New  Jersey.  A  gray  or  bluish- 
gray  and  green  variety  occurs  near  Edenville. 

The  word  tourmaline  is  a  corruption  of  the  name  in  Ceylon, 
whence  it  was  first  brought  to  Europe.  Lyncurium  is  sup- 
posed to  be  the  ancient  name  for  common  tourmaline  ;  and 
the  red  variety  wras  probably  called  hyacinth. 

Uses.  The  red  tourmalines,  when  transparent  and  free 
from  cracks,  such  as  have  been  obtained  at  Paris,  Me.,  are 
of  great  value  and  afford  gems  of  remarkable  beauty.  They 
have  all  the  richness  of  color  and  luster  belonging  to  the 
ruby,  though  measuring  an  inch  across.  A  Siberian  speci- 
men of  this  variety,  now  in  the  British  museum,  is  valued  at 
£500.  The  yellow  tourmaline,  from  Ceylon  is  but  little  in- 
ferior to  the  real  topaz,  and  is  often  sold  for  that  gem.  The 
green  specimens,  when  clear  and  fine,  are  also  valuable  for 
gems.  A  stone  measuring  6  lines  by  4,  of  a  deep  green 
color,  is  valued  at  Paris  at  815  to  $20.  The  thin  crystals 
of  Grafton,  N.  H.  are  transparent,  and  may  be  used  as  sug- 
gested by  B.  Silliman,  Jr.,  in  polarizing  instruments. 

Where  have  fine  specimens  cf  red  and  green  tourmaline  been  fonnd 
in  the  United  States  ?  What  is  said  of  yellow  tourmaline  1  What  is 
the  value  of  tourmaline  as  a  gun  ? 


190  A.LUMINA* 


AXINITE. 

Triclinate,  In  acute  edged  oblique  rhomboidai  prisms ; 
P  :  M  =  134^  40,  P  :  T  =  115°  5,  M  :  T  = 
135°  10'.  Cleavage  indistinct.  Also  rarely 
massive  or  lamellar. 

Color  clove   brown;  differing    somewhat  in' 
shade  in  two  directfons.  Luster  vitreous.  Trans- 
parent to  subtranslucent.     Brittle.     H  =  6'5 — 
7.     Gr  =  3-27.     Pyro-electric. 

Composition  :  silica  45,  alumina  19,  lime  12*5,  peroxyd  of 
iron  12-25,  peroxyd  of  manganese  9,  boracic  acid  2*0,  mag- 
nesia 0*2.  In  another  specimen  5*6  per  cent,  of  boracic 
acid  were  found.  Before  the  blowpipe  fuses  readily  with  in- 
tumescence to  a  dark  green  glass,  which  becomes  black  in 
the  oxydating  flame. 

Dif.  Remarkable  for  the  sharp  thin  edges  of  its  crystals, 
and  its  glassy  brilliant  appearance,  without  cleavage.  The 
crystals  are  implanted,  and  not  disseminated  like  garnet.  In. 
one  or  all  of  these  particulars,  and  also  in  blowpipe  reaction, 
it  differs  from  any  of  the  titanium  ores, 

Obs.  St.  Cristophe  in  Dauphiny,  is  a  fine  locality  of  this 
mineral.  It  occurs  also  at  Kongsberg  in  Norway,  Normark 
in  Sweden,  and  Cornwall,  England ;  also  Thum  in  Saxony, 
whence  the  name  Thummerstein  and  Thumite. 

In  the  United  States,  it  has  been  found  at  Phippsburg  in 
Maine,  by  Dr.  C.  T.  Jackson. 

IOLITE. — Dichroite,  Cordierite. 

Trimetric.  In  rhombic  and  hexagonal  prisms.  Usually 
occurs  in  six  or  twelve-sided  prisms,  or  disseminated  in 
masses  without  distinct  form.  Cleavage  indistinct ;  but 
crystals  often  separable  into  layers  parallel  to  the  base. 

Color  various  shades  of  blue  ;  often  deep  blue  in  the  di- 
rection of  the  axis,  and  yellowish-gray  transversely.  Streak 
uncolored.  Luster  and  appearance  much  like  that  of  glass. 
Transparent  to  translucent.  Brittle.  H  =  7  — -7-5.  Gr  = 
2-6—2-7. 

Composition  of  a  specimen  from  Haddam,  Ct. :  silica  48-3, 

What  is  the  form  and  color  of  axinite  ?  What  characters  distinguish 
it  ?  Why  was  it  so  called  ?  What  are  the  forms  of  iolite  I  What 
are  its  colors,  appearance  and  hardness  1 


MICA.  191 

alumina  32-5,  magnesia  10,  protoxyd  of  iron  6'0,  protoxyd 
of  manganese  0*1,  water  (hygrometric)  3'1.  Before  the 
blowpipe  fuses  on  the  edges  with  difficulty  to  a  blue  glass 
resembling  the  mineral. 

Dif.  The  glassy  appearance  of  iolite  is  so  peculiar  that 
it  can  be  confounded  with  nothing  but  blue  quartz,  from 
which  it  is  distinguished  by  its  fusing  on  the  edges.  It  is 
easily  scratched  by  sapphire. 

Obs.  Found  at  .Haddam,  Conn.,  in  granite  ;  also  in  gneiss 
at  Brimfield,  Mass.  ;  at  Richmond,  N.  H.,  in  talcose  rock. 
The  principal  foreign  localities  are  at  Bodenmais  in  Bava- 
ria ;  Arendal,  Norway ;  Capo  de  Gata,  Spain ;  Tunaberg, 
Finland  ;  also  Norway,  Greenland  and  Ceylon. 

The  name  iolite  is  from  the  Greek  iodes,  violet,  alluding 
to  its  color ;  it  is  also  called  dichroite,  from  dis,  twice,  and 
chroa,  color,  owing  to  its  having  different  colors  in  two 
directions. 

Uses.  Occasionally  employed  as  an  ornamental  stone ; 
when  cut  it  presents  different  shades  of  color  in  different 
directions. 

NOTE. — Iolite  exposed  to  the  air  and  moisture  undergoes  a  gradual 
alteration,  becoming  a  hydrate  (absorbing  water)  and  assuming  a  foli- 
ated micaceous  structure,  so  as  to  resemble  talc,  though  more  brittle 
and  hardly  greasy  in  feel.  Hydrous  iolite,  chlorophyllite,  and  esmark- 
ite,  are  names  that  have  been  given  to  the  altered  iolite  ;  andfahlunite 
and  gigantolite  are  probably  of  the  same  origin.  (See  pages  162, 163.) 

MICA. — Muscovite. 

Monoclinate.     In  oblique  rhombic  prisms  of  about  120° 
and   60 D,    P   on   M    98°   40' ;    sometimes 
114° — 115\      Crystals   usually   with    the 
i  acute  edge  replaced.     Cleavage    eminent, 
parallel   to  P,  yielding  easily  thin  elastic 
laminae  of  extreme  tenuity.     Usually  in  thinly  foliated  masses, 
j  plates  or  scales.     Sometimes  in  radiated  groups  of  aggre- 
gated scales  or  small  folia. 

Colors  from  white  through  green,  yellowish  and  brownish 
shades  to  black.  Luster  more  or  less  pearly.  Transparent 
or  translucent.  Tough  and  elastic.  H=2 — 2'5.  Gr= 
2-8—3. 

Composition  :  silica  46-3,  alumina  36-8,  potash  9'2,  per- 

How  is  iolite  distinguished  from  quartz  and  sapphire  ?     Why  was  it 
j  called  iolite  and  dichroite  ?  Describe  mica.   What  is  its  composition  ? 


192  ALUMINA. 

oxyd  of  iron  4'5,  fluoric  acid  0*7,  water  1-8.     Before  the 
blowpipe  infusible,  but  becomes  opaque  white. 

Varieties. — A  variety  in  which  the  scales  are  arranged  in 
a  plumose  form  is  called  plumose  mica ;  another,  in  which 
the  plates  have  a  transverse  cleavage,  has  been  termed  pris- 
matic mica. 

Dif.  Mica  differs  from  talc  in  affording  thinner  folia  and 
being  elastic  ;  also  in  not  having  the  greasy  feel  of  that 
mineral.  The  same  characters,  excepting  the  last,  distin- 
guish it  from  gypsum  ;  besides,  it  does  not  crumble  so  readily 
on  heating. 

Obs.  Mica  is  one  of  the  constituents  of  granite,  gneiss 
and  mica  slate,  and  gives  to  the  latter  its  laminate  structure. 
It  also  occurs  in  granular  limestone.  Plates  two  and  three 
feet  in  diameter,  and  perfectly  transparent,  are  obtained  at 
Alstead,  Acworth  and  Grafton,  New  Hampshire.  Other 
good  localities  are  Paris,  Me.  ;  Chesterfield,  Barre,  Brim- 
field,  and  South  Royalston,  Mass. ;  near  Greenwood  furnace, 
Warwick  and  Edenville,  Orange  county,  and  in  Jefferson 
and  St.  Lawrence  counties,  N.  Y.  ;  Newton  and  Franklin, 
N.  J.  ;  near  Gerrnantown,  Pa.,  and  Jones's  Falls,  Maryland. 
Oblique  prisms  from  near  Greenwood  are  sometimes  six  or 
seven  inches  in  diameter. 

A  green  variety  occurs  at  Unity,  Maine,  near  Baltimore, 
Md.,  and  at  Chestnut  Hill,  Pa.  Prismatic  mica  is  found  at 
Russel,  Mass. 

Uses.  Mica,  on  account  of  the  toughness,  transparency 
and  the  thinness  of  its  folia,  has  been  used  in  Siberia  for  glass 
in  windows  :  whence  it  has  been  called  Muscovy  glass.  It 
was  formerly  employed  in  the  Russian  navy,  because  not 
liable  to  fracture  from  concussion.  It  is  in  common  use  for 
lanterns,  and  also  for  the  doors  of  stoves.  It  affords  a  con- 
venient material  for  preserving  minute  objects  for  the  micros- 
cope, and  is  sometimes  used  for  holding  minerals  before  the 
blowpipe  flame. 

The  best  localities  of  the  mineral  in  this  country  for  tho 
arts,  are  those  of  New  Hampshire. 

Lepidolite,  or  Lithia  mica.  Occurs  in  crystals  or  laminae,  of  a  pur- 
plish color,  and  often  in  masses  consisting  of  aggregated  scales.  A 
specimen  from  the  Ural  consisted,  according  to  Rosales,  of  silica  47' 7, 


How  does  mica  differ  from  talc  and  gypsum  ?  Of  what  rocks  is 
it  a  constituent?  What  are  its  uses?  What  is  the  peculiarity  of 
lepidolite  ? 


MICA.  193 


alumina  20'3,  l;me  6'1,  protoxyd  of  manganese  47,  potash  ll'O,  lithia 
28,  soda  22,  fluorine  10'2,  chlorine  1-2. 

Lepidolite  occurs  at  the  albite  vein  in  Chesterfield,  Mass.,  and  at 
Goshen  in  the  same  state  ;  also  at  Paris,  Me.,  with  red  tourmalines,  and 
near  Middletown,  Ct. 

Fachsite.  A  green  mica  from  the  Zillerthal,  containing  nearly  4 
per  cent,  of  oxyd  of  chromium. 

From  the  crystallization  of  mica,  two  additional  species  have  been 
made  out  of  the  old  species  so  called.  The  common  mica,  as  above 
described,  has  an  oblique  prism  for  its  primary.  Many  micas,  when  in 
perfect  crystals,  have  the  form  of  a  hexagonal  prism, 
and  but  one  axis  of  polarization,  (see  page  60,)  this  ^^  P 
last  fact  proving  the  primary  to  be  a  regular  hexago- 
nal prism.  This  species  is  properly  distinguished, 
and  has  been  called  hexagonal  mica.  The  mica  of 
Middletown,  Conn.,  and  of  many  other  localities  not  yet  particularly 
ascertained,  belongs  to  this  species.  So  also  the  dark  colored  micas  ot 
Siberia,  and  the  brilliant  hexagonal  crystals  of  Vesuvius. 

There   are  also  hexagonal  crystals  which  have  been  found  by  Dove 
to  have  two  axes  of  polarization,  this  indicating  that 
the  lateral  axes  of  the  primary  are  unequal,  and  that  ^^     P 
the  form  is  a  rhombic  prism  with  the  acute  edges 
truncated.     These  crystals  are  from  Henderso/i,  Jef- 
ferson county,  N.  Y.     The  species  is  called  rhombic 
•  mica ,  or  phlogophite, 

Margarile,  or  Pearl  mica.  In  hexagonal  prisms,  having  the  struc- 
ture of  mica  ;  and  also  in  intersecting  lamina;.  Luster  pearly,  approach- 
ing talc,  but  differing  from  that  mineral  in  being  a  silicate  of  alumina 
instead  of  magnesia.  Color  nearly  white,  or  gray.  It  intumesces  and 
fuj-es  before  the  blowpipe.  From  Sterzing  in  the  Tyrol,  associated  with 
chlorite. 

Emeiylitc  and  Euphyllite  arc  new  species  related  somewhat  to  mar- 
ganite,  an^j  found  asso-iated  with  poruridum  in  Pennsylvania  and  else- 
where. They  are  rather  brittle. 

Nacrite.  Different  compounds  are  included  under  this  name,  which 
agree  in  resembling  a  whitish  soft  earthy  talc,  with  a  greasy  feel,  and  in 
containing  no  magnesia,  or  but  a  few  per  cent,  only  of  that  earth.  Occurs 
massive,  consisting  of  minute  scales.  A  kind  from  Brunswick,  Me., 
contains  silica  64'5,  alumina  28  9,  protoxyd  of  iron  4*4  ;  another  from 
the  Alps,  consists  of  silica  50'0,  alumina  26'0,  potash  17 '5,  lime  1-5, 
peroxyd  ofiron  50. 

Margarodite,  or  Schistose  talc  of  Zillerthal  is  a  variety  of  common 
mica. 

Lcpidomelane.  A  black  iron-mica,  occurring  in  six-sided  scales  or 
tables  aggregated  together.  It  contains  silica  374,  alumina  11*6,  per- 
oxyd ofiron  277,  protoxyd  ofiron  12'4,  magnesia  and  lime  03,  potash 
9  2,  water  0-6.  From  Warmland.  Ottrelite  (which  includes  the  phyl- 
lite  from  Sterling,  Mass.,)  is  an  allied  mineral  occurring  in  black  scales, 
disseminated  through  the  rock. 


What  are  other  kinds  of  mica  ? 
17 


194  ALUMINA. 

5.     Combination  of  a  Silicate  and  Fluorid. 

TOPAZ. 

Tri metric.     In  right  rhombic  prisms,  usually  differently 
modified  at  the  two  extremities.     Pyro-electric. 
M  :  M=124°  19'.     Cleavage  perfect,  parallel  to 
the  base. 

Color  pale  yellow  ;  sometimes  greenish,  blu- 
ish, or  reddish.  Streak  white.  Luster  vitreous. 
Transparent  to  subtranslucent.  Fracture  sub- 
conchoidal,  uneven. 

Composition :  silica  34-2,  alumina  57*5,  fluoric  acid  7'8. 
Infusible  alone  on  charcoal  before  the  blowpipe.  Some 
varieties  are  changed  by  heat  to  a  wine  yellow  or  pink  tinge. 

Dif.  Topaz  is  readily  distinguished  from  tourmaline 
and  other  minerals  it  resembles  by  its  brilliant  transverse 
cleavage. 

Ohs.  Pycnite  has  been  separated  from  this  species.  I 
differs  from  topaz  mainly  in  the  state  of  aggregation  of  the 
particles,  it  presenting  a  thin  columnar  structure  and  forming 
masses  imbedded  in  quartz.  The  physalite  or  pyrophysalite 
of  Hisinger,  is  a  coarse,  nearly  opaque  variety,  found  in 
yellowish- white  crystals  of  considerable  dimensions.  This 
variety  intumcsces  when  heated,  and  hence  its  name  from 
phusao,  to  blow. 

Topaz  is  confined  to  primitive  regions,  and  commonly 
occurs  in  granite,  associated  with  tourmaline,  beryl,  occa- 
sionally with  apatite,  fluor  spar,  and  tin.  With  quartz,  tour- 
maline, and  lithomarge,  it  forms  the  mixture  called  topaz 
rock  by  Werner. 

Fine  topazes  are  brought  from  the  Uralian  and  Altai 
mountains,  Siberia,  and  from  Kamschatka,  where  they  occur 
of  green  and  blue  colors.  In  Brazil  they  are  found  of  a  deep 
yellow  color,  either  in  veins  or  nests  in  lithomarge,  or  in 
loose  crystals  or  pebbles.  Magnificent  crystals  of  a  sky-blue 
color  have  been  obtained  in  the  district  of  Cairngorum,  in 
Aberdeenshire.  The  tin  mines  of  Schlaggenwald,  Zinnwald, 
and  Ehrenfriedersdorf  in  Bohemia,  St.  Michael's  Mount  in 


What  are  the  forms  and  cleavage  of  topaz  crystals?  .-What  are  their 
colors  1  their  luster  and  hardness  ?  their  composition  ?  How  is  topaz 
distinguished  from  tourmaline  and  other  minerals'?  How  does  topaz 
occur  ? 


TOPAZ.  195 

Cornwall,  etc.,  afford  smaller  crystals.  The  physalite  varie- 
ty occurs  in  crystals  of  immense  size  at  Finbo,  Sweden,  in 
a  granite  quarry,  and  at  Broddbo,  in  a  boulder.  A  well 
defined  crystal  from  this  locality,  in  the  possession  of  the 
<_  Village  of  Mines  of  Stockholm,  weighs  eighty  pounds.  Al- 
tenberg  in  Saxony,  is  the  principal  locality  of  pycnite.  It  is 
there  associated  with  quartz  and  mica. 

Trumbull.  Conn.,  is  the  principal  locality  of  this  species  in 
the  United  States.  It  seldom  affords  fine  transparent  crystals, 
except  of  a  small  size  :  these  are  usually  white ;  occa- 
sionally with  a  tinge  of  green  or  yellow.  The  large  coarse 
crystals  sometimes  attain  a  diameter  of  several  inches, 
(rarely  six  or  seven,)  but  they  are  deficient  in  luster,  usually 
of  a  dull  yellow  color,  though  occasionally  white,  and  often 
are  nearly  opaque. 

The  ancient  topazion  was  found  on  an  island  in  the  Red 
Sea,  which  was  often  surrounded  with  fog,  and  therefore 
difficult  to  find.  It  was  hence  named  from  topazo,  to  seek. 
This  name,  like  most  of  the  mineralogical  terms  of  the  an- 
cients, was  applied  to  several  distinct  species.  Pliny  de- 
scribes a  statue  of  Arsinoe,  the  wife  of  Ptolemy  Philadelphus, 
four  cubits  high,  which  was  made  of  topazion,  or  topaz,  but 
evidently  not  the  topaz  of  the  present  day,  nor  chrysolite, 
which  has  been  supposed  to  be  the  ancient  topaz.  It  has 
been  conjectured  that  it  was  a  jaspe-r  or  agate ;  others  have 
imagined  it  to  be  prase,  or  chrysoprase. 

Uses.  Topaz  is  employed  in  jewelry,  and  for  this  purpose 
its  color  is  often  altered  by  heat.  The  variety  from  Brazil 
assumes  a  pink  or  red  hue,  so  nearly  resembling  the  Balas 
ruby,  that  it  can  only  be  distinguished  by  the  facility  with 
which  it  becomes  electric  by  friction.  The  finest  crystals  for 
the  lapidary  are  brought  from  Minas  Novas,  in  Brazil.  From 
their  peculiar  limpidity,  topaz  pebbles  are  sometimes  denomi- 
nated gouttes  d'eau.  When  cut  with  facets  and  set  in  rings, 
they  are  readily  mistaken,  if  viewed  by  daylight,  for  diamonds. 
The  coarse  varieties  of  topaz  may  be  employed  as  a  substi- 
tute for  emery  in  grinding  and  polishing  hard  substances. 

Topaz  is  cut  on  a  leaden  wheel,  and  is  polished  on  a  cop- 
per wheel  with  rotten  stone.  It  is  usually  cut  in  the  form 
of  the  brilliant  or  table,  and  is  set  either  with  gold  foil  or  a 
jour.  The  white  and  rose -red  are  most  esteemed. 


What  are  the  uses  of  topaz  ?     What  is  the  effect  of  heat  ? 


196  ALUMINA. 

6.     Combination  of  a  Silicate  and  Sulphate. 
LAPIS-LAZULI.- — Ultramarine. 

Monometric.  In  dodecahedrons.  Cleavage  imperfect. 
Also  massive.  Color  rich  Berlin  or  azure 
blue.  Luster  vitreous.  Translucent  to  opaque. 
H=5-5.  Gr=2-5— 2-9. 

Composition :  silica  45*5,  alumina  31'8, 
soda  9'1,  lime  3*5,  iron  0'8,  sulphuric  acid 
5'9,  sulphur  0-9,  chlorine  0'4,  water  O'l. 
Fuses  to  a  white  translucent  or  opaque  glass,  and  if  calcined 
and  reduced  to  powder  loses  its  color  in  acids.  The  color 
of  the  mineral  is  supposed  to  be  due  to  sulphuret  of  sodium. 
Dif.  Distinguished  from  azurite  by  its  hardness  and  by 
giving  no  indications  of  copper  before  the  blowpipe  ;  and 
from  lazulite  by  its  fusibility,  hardness,  and  not  giving  the 
reaction  of  phosphoric  acid. 

Obs.  Found  in  granite  and  granular  limestone,  and  is 
brought  from  Persia,  China,  Siberia,  and  Bucharia.  The 
specimens  often  contain  scales  of  mica  and  disseminated 
pyrites. 

Uses.  The  richly-colored  lapis  lazuli  is  highly  esteemed 
for  costly  vases,  and  for  inlaid  work  in  ornamental  furniture. 
Magnificent  slabs  are  contained  in  some  of  the  Italian  cath- 
edrals. It  is  also  used  in  the  manufacture  of  mosaics. 
When  powdered  it  constitutes  the  most  beautiful  and  most 
durable  of  blue  paints,  called  ultramarine^  and  has  been  one 
of  the  most  costly  colors.  The  late  discovery  of  a  mode  of 
making  an  artificial  ultramarine,  quite  equal  to  the  native, 
has  afforded  a  substitute  at  a  comparatively  cheap  rate. 
This  artificial  ultramarine  consists  of  silica  45'6,  alumina 
23-3,  soda  21 '5,  potash  1*7,  lime  trace,  sulphuric  acid  3'8, 
sulphur  1-7,  iron  I'l,  and  chlorine  a  small  quantity  unde- 
termined. It  has  taken  the  place  in  the  arts,  entirely,  of  the 
native  lapis-lazuli. 

Hauyne,  (including  nosean  and  spinellane.}  In  dodecahedrons,  and 
allied  to  the  preceding.  Color  bright  blue,  occasionally  greenish. 
Transparent  to  translucent.  H=6.  Gr=2'68 — 3  35.  Composition, 


What  is  the  crystalline  form  of  lapis-lazuli  ?  What  is  its  color  ?  its 
hardness?  its  composition  1  How  is  it  distinguished  from  apatite  and 
lazulite  1  How  does  it  cncur  ?  What  are  its  uses?  What  is  said  of 
the  artificial  ultramarine  1 


BERYL.  197 

silica  35-0,  alumina  27'4,  soda  9'1,  lime  12  6,  sulphuric  acid  12'6,  with 
traces  of  chlorine,  sulphur  and  water.  The  nosean  afforded  silica  35'9, 
alumina  32'6,  soda  IT'S,  sulphuric  acid  9-2,  with  a  small  per-centage 
of  other  ingredients.  A  variety  from  Litchh'eld,  Maine,  aJBbrded  Dr. 
Jackson  nearly  the  same  proportions — silica  35'4,  alumina  31'75,  soda 
176,  sulphuric  acid  65,  with  oxyd  of  manganese  4'4,  and  lime  1-8. 
Hauyne  comes  from  the  Vesuvian  lavas  and  near  Rome.  The  nosean 
is  found  in  blocks  with  feldspar  mica  and  zircon  on  the  Rhine,  near 
the  Laacher  See.  Also  at  Litchfield,  Maine. 

7.     Silicate  with  a  CJdorid. 
SODALITE. 

In  dodecahedrons  like  lapis-lazuli.  Color  brown,  gray,  or 
blue.  H=i6.  Gr=2-25— 2-3. 

Composition  :  silica  36,  alumina  32'6,  soda  26*5,  muriatic 
acid  5'3. 

From  Greenland,  Vesuvius  and  Brisgau. 


5.    GLUCINA. 

The  minerals  containing  glucina  are  above  quartz  (7) 
in  hardness,  excepting  one.  (leucophane,)  which  contains 
largely  of  lime.  The  specific  gravity  is  between  2'7  and 
3*75.  Excepting  leucophane,  they  fuse  before  the  blowpipe 
with  extreme  difficulty,  or  not  at  all. 

BERYL.  —  Emerald. 


Hexagonal.     In  hexagonal  prisms.     Usually  in  long,  stout 
prisms,  without  regular  terminations.     Cleavage 
jbasal,  not  very  distinct  ;  rarely  massive. 

Color  green,  passing  into  blue  and  yellow  ; 
color  rather  pale,  excepting  the  deep  and  rich 
green  of  the  emerald.  Streak  uncolored.  Luster 
vitreous  ;  sometimes  resinous.  Transparent  to 
subtranslucent.  Brittle.  H  =  7'5  —  8.  Gr= 
2-65—  2-75. 

Varieties  and  Composition.  The  emerald  includes  the 
rich  green  variety;  it  owes  its  color  to  oxyd  of  chrome. 
Beryl  especially  includes  the  paler  varieties,  which  are  col- 


What  is  sodalite  ?     What  is  said  of  minerals  containing  glucina  ? 
What  is  the  crystalline  form  of  beryl  ?   it  colors  and  hardness  ? 
17* 


198  GLUCINA, 


ored  by  oxyd  of  iron.     Aquamarine  includes  clear  beryls  of 
a  sea-green,  or  pale-bluish  or  bluish-green  tint. 

The  beryl  consists  of  silica  66-5,  alumina  16'8,  glucina 
15*5,  peroxyd  of  iron  O6.  Emerald  contains  less  than  one 
per  cent,  of  oxyd  of  chromium.  Before  the  blowpipe  be- 
comes  clouded,  but  fuses  on  the  edges  with  difficulty. 

Dif.  The  hardness  distinguishes  this  species  from  apa- 
tite ;  and  this  character,  and  also  the  form  of  the  crystals, 
from  green  tourmaline  ;  the  imperfect  cleavage,  from  euclase 
and  topaz. 

Obs.  The  finest  emeralds  come  from  Grenada,  where 
they  occur  in  dolomite.  A  crystal  from  this  locality,  two 
inches  long  and  about  an  inch  in  diameter,  is  in  the  cabinet 
ef  the  Duke  of  Devonshire.  It  weighs  8  oz.  18  dwts.,  and 
though  containing  numerous  flaws,  and  therefore  but  partially 
fit  for  jewelry,  has  been  valued  at  150  guineas.  A  more 
splendid  specimen,  but  weighing  only  6  oz.,  is  in  the  pos- 
session of  Mr.  Hope  of  London.  It  cost  .£500.  Emeralds 
of  less  beauty,  but  of  gigantic  size,  occur  in  Siberia.  One 
specimen  in  the  royal  collection  of  Russia  measures  4£ 
inches  in  length  and  12  in  breadth,  and  weighs  26f  pounds 
troy.  Another  is  7  inches  long  and  4  broad,  and  weighs  6 
pounds.  Mount  Zalora  in  Upper  Egypt,  affords  a  less  dis- 
tinct variety. 

The  finest  beryls  (aquamarines,)  come  from  Siberia,  Hin- 
dostan  and  Brazil.     One  specimen  belonging  to  Don  Pedro 
is  as  large  as  the  head  of  a  calf,  and  weighs  225  ounces,  or ' 
more  than  18£  pounds  troy  ;  it  is  transparent  and  without  a 
flaw. 

In  the  United  States,  beryls  of  enormous  size  have  been 
obtained,  but  seldom  transparent  crystals.  They  occur  in 
granite  or  gneiss.  One  hexagonal  prism  from  Acworth,  N. 
H.,  weighed  240  pounds  and  measured  4  feet  in  length,  with 
the  lateral  faces  5£  inches  in  breadth ;  it  color  was  bluish- 
green,  excepting  a  part  at  one  extremity,  which  was  dull 
green  and  yellow.  At  Royalston,  Mass.,  one  crystal  has 
been  obtained  a  foot  long,  and  pellucid  crystals  are  some- 
times met  with.  Haddam,  Conn.,  has  afforded  fine  crystals, 

What  is  the  composition  of  beryl  1  What  are  the  different  varieties 
and  their  distinctions?  How  is  beryl  distinguished  from  apatite  and 
tourmaline?  Where  are  the  finest  emeralds  brought  from?  What  is 
said  of  the  Siberian  emeralds  ?  What  of  the  finest  beryls  ?  What  is 
the  size  of  some  beryls  found  in  the  United  States  ? 


EUCLASE, 


199 


(see  the  figure.)     Other   localities   are    Barre,  Fitchburg, 
Goshen,  Mass. ;  Albany,  Norwich,  Bowdoinham  andTopham, 
Me. ;  Wilmot,  N.  H. ;  Monroe,  Conn.  ;  Leyperville,  Penn. 
The  name  beryl  is  from  the  Greek  beryllos. 

EUCLASE. 

Triclinate.  In  right  rhomboidal  prisms;  M  :  T  =  130° 
50'.  Cleavage  in  one  direction  highly  perfect,  affording 
smooth  polished  faces. 

Color  pale  green.  Luster  vitreous  ;  transparent.  Very 
brittle.  H  =  7-5.  Gr  =  2-9— 3-1.  Pyro-electric. 

Composition  :  silica  43-2,  alumina  30*6,  glucina  21 '8,  per- 
oxyd  of  iron  2-2,  oxyd  of  tin  0'7.  Before  the  blowpipe  with  a 
strong  heat  it  intumesces,  and  finally  fuses  to  a  white  enamel. 

Dif.  The  very  perfect  cleavage  of  this  glassy  mineral  is 
like  that  of  topaz,  and  at  once  distinguishes  it  from  tourma- 
line and  beryl.  It  differs  from  topaz  in  its  very  oblique 
crystals. 

Obs.     Occurs  in  Peru,  and  with  topaz  in  Brazil. 

Uses.  The  crystals  of  this  mineral  are  elegant  gems  of 
themselves,  but  they  are  seldom  cut  for  jewelry  on  account 
of  their  brittleness. 

CHRYSOBERYL. 

Trimetric.  In  modified  rectangular  prisms. 
7'.  M  :  e=125J  20'.  Cleavage 
not  very  distinct,  parallel  to  M. 
Also  in  compound  crystals,  as  in 
fig.  2.  Crystals  sometimes  thick  ; 
often  tabular. 

Color  bright  green,  from  a  light 
shade  to  emerald  green ;  rarely 
raspberry  or  columbine  red  by  transmitted  light.  Streak 
uncolored.  Luster  vitreous.  Transparent  to  translucent. 
H=r8-5.  Gr  =  3-5— 3-8. 

Composition  of  a  species  from  Haddam,  according  to 
Seybert,  alumina  73*6,  glucina  15*8,  silica  4*0,  protoxyd  of 
iron  3 '4.  Infusible  and  unaltered  before  the  blowpipe. 

Alexandrite  is  a  name  given  to  an  emerald-green  variety 
from  the  Urals,  which  is  supposed  to  be  colored  by  chrome, 

What  is  the  form  and  cleavage  of  euclase  ?  what  the  color  and  luster  ? 
How  is  it  distinguished  ?  What  are  its  uses?  What  is  the  appearance 
of  chrysoberyl?  its  hardness?  its  composition ?  What  is  alexandrite  ? 


200  ZISCONIA. 

and  to  bear  the  same  relation  to  ordinary  chrysoberyl  as 
emerald  to  beryl. 

Dif.  Near  beryl,  but  distinct  in  its  often  tabular  crystal- 
lizations,  and  its  entire  infusibility. 

Obs.  Chrysoberyl  occurs  in  the  United  States  in  granite 
at  Haddam,  Conn.,  and  Greenfield,  near  Saratoga,  N.  Y., 
associated  with  beryl,  garnet,  etc. 

The  name  chrysoberyl  is  from  the  Greek  chrysos,  golden, 
and  beryllos,  beryl.  Cymophane  is  another  name  of  the 
species,  alluding  to  its  opalescence,  and  derived  from  the 
Greek  kuma,  wave,  and  phaino,  to  appear. 

Uses.  The  crystals  are  seldom  sufficiently  pellucid  and 
clear  from  flaws  to  be  valued  in  jewelry  ;  but  when  of  fine 
quality,  it  forms  a  beautiful  gem,  and  is  often  opalescent. 

Phenacite.  Colorless  or  bright  wine-yellow,  inclining  to  red,  of 
vitreous  luster  and  transparent  to  opaque.  Crystals  and  cleavage  rhom- 
bohedral.  H=8.  Gr=2'97.  Composition,  silica  55'1,  glucina  44'5, 
with  a  trace  of  magnesia  and  alumina.  Unaltered  before  the  blowpipe. 
From  Perm,  Siberia,  with  emerald. 

Leucophane.  Resembles  somewhat  a  light  green  apatite.  H=3'5. 
Gr=2-97.  Powder  phosphorescent.  Pyro-electric.  Composition,  silica 
47'8,  glucina  1T5,  lime  25-0,  protoxyd  of  manganese  T01,  potassium 
0'3,  sodium  7'6,  fluorine  6'2.  From  Norway  in  syenite,  accompanying 
albite  and  dfeolite. 

Hclvin.  Helvin  occurs  in  Saxony  and  Norway  in  tetrahedrons  of  a 
wax  yellow  or  brownish  color.  H=6 — 6'5.  Gr=3'l — 3-3.  Luster 
vitreous.  It  contains  silica,  oxyds  of  iron  and  manganese,  sulphuret  of 
manganese,  with  glucina  and  alumina. 

6.     ZIRCONIA. 

ZIRCON. 

Dimetric.  In  square  prisms  and  octahedrons.  M  :  e  = 
132°  10  ;  e  :  e  =  123°  19'.  Cleavage  parallel  to 
M,  but  not  strongly  marked.  Usually  in  crystals  ; 
but  also  granular. 

Color  brownish-red,  brown,  and  red,  of  clear 
tints  ;  also  yellow,  gray  and  white.     Streak  un- 
colored.     Luster  more  or  less  adamantine.    Often 
transparent ;  also  nearly  opaque.     Fracture  con- 
choidal,  brilliant.     H=7-5.     Gi— 4-5—4-8. 

How  does  chrysoberyl  differ  from  beryl  ?  Where  and  how  does  it 
occur  ?  What  is  the  origin  of  the  name  chrysoberyl  ]  What  are  its 
uses?  Describe  zircon  ? 


ZIRCOX.  201 

Varieties  and  Composition.  Transparent  red  specimens 
are  called  Jiyacinili.  A  colorless  variety  from  Ceylon,  hav- 
ing a  smoky  tinge,  is  called  jargon;  it  is  sold  for  inferior 
di.»in.'w!s.  which  it  resembles,  though  much  less  hard.  The 
name  zirconile  is  sometimes  applied  to  crystals  of  gray  or 
brownish  tints.  Consists  of  silica  33*5,  zirconia  67"2.  In- 
fusible before  the  blowpipe,  but  loses  color.  Forms  with 
borax  a  diaphanous  glass. 

Dif.  The  hyacinth  is  readily  distinguished  from  spinel 
by  its  prismatic  form  and  specific  gravity,  as  well  as  its 
adamantine  luster  and  a  less  clear  shade  of  red.  Its  infusi- 
bility,  hardness,  and  other  characters,  distinguish  it  from 
tourmaline,  idocrase,  staurotide,  and  the  minerals  it  re- 
sembles. 

Obs.  The  zircon  is  confined  to  the  crystalline  rocks,  in- 
cluding lavas  and  granular  limestone.  Hyacinth  occurs 
mostly  in  grains,  and  comes  from  Ceylon,  Auvergne,  Bohe- 
mia, and  elsewhere  in  Europe.  Siberia  affords  crystals  as 
large  as  walnuts.  Splendid  specimens  come  from  Greenland. 

In  the  United  States,  fine  crystals  of  zircon  occur  in  Bun- 
combe county,  N.  C. ;  of  a  cinnamon  red  color  in  Moria,  Es- 
sex county,  N.  Y.  ;  also  at  Two  ponds  and  elsewhere,  Orange 
county,  in  crystals  sometimes  an  inch  and  a, half  long;  in 
Hammond,  St.  Lawrence  county,  and  Johnsbury,  Warren 
county,  N.  Y.  ;  at  Franklin,  N.  J.  ;  in  Litchfield,  Me.  ;  Mid- 
dlebury,  Vt. ;  Haddam  and  Norwich,  Conn. 

The  name  hyacinth  is  from  the  Greek  huakinthos.  But 
it  is  doubtful  whether  it  was  applied  by  the  ancients  to  stones 
of  the  zircon  species. 

Uses.  The  clear  crystals  (hyacinths)  are  of  common  use 
in  jewelry.  When  heated  in  a  crucible  with  lime,  they  lose 
their  color,  and  resemble  a  pale  straw-yellow  diamond,  for 
which  they  are  substituted.  Zircon  is  also  used  in  jewelling 
watches.  The  hyacinth  of  commerce  is  to  a  great  extent 
cinnamon  sfone,  a  variety  of  garnet. 

The  earth  zirconia  is  also  found  in  the  rare  minerals  eudialyte  and 
wQhlerite  ;  also  in  polymignite,  aschynite,  iBrstedite  ;  also  sparingly  in 
fergusonite. 


What  is  the  composition  of  zircon  ?  What  are  its  varieties?  How 
does  it  differ  from  spinel  and  other  minerals?  How  does  it  occur? 
What  is  said  of  its  uses  ?  Does  the  earth  zirconia  occur  in  other  min- 
erals? 


202  METALS. 

Eudialyte.  In  modified  acute  rhombohedrons  ;  vitreous  and  of  a  red 
color.  R  :  R  =  73°  40'.  Transverse  cleavage,  perfect;  opaque  of 
nearly  so.  It  is  a  silicate  of  zirconia,  lime,  soda  and  iron,  and  gelatin- 
izes in  acids.  From  West  Greenland,  in  white  feldspar. 

Wohleriie.  In  tabular  crystals  of  light  yellow  and  brownish  shades  ; 
sometimes  transparent.  Consists  mainly  of  silica,  columbic  acid,  zirco- 
nia, (15  per  cent.,)  lime  and  soda.  From  Brevig,  Norway. 

JEschynite.  A  titanate  of  zirconia  and  oxyd  of  cerium,  with  some 
lime  and  oxyd  of  iron.  Black  and  subrnetallic,  or  resinous  in  luster.; 
H=5— 6.  Gr=5- 1—5-7.  From  the  Ural. 

GBrstedite.  A  titanate  and  silicate  of  zirconia.  Color  brown. 
H=6'5.  Gr=3.629,  In  brilliant  crystals  from  Arendal,  Norway. 

Malacone.  Contains  silica  3T3.  zirconia  63'4,  with  water  3.  Form 
that  of  zircon.  Gr=3'9.  H=6.  Appears  to  be  a  zircon  containing 
water.  Color  bluish  white,  brownish,  reddish.  Streak  colorless. 

7.     THORIA. 

The  earth  Thoria  has  been  found  only  in  a  rare  mineral 
named  from  its  constitution  thorite,  and  in  the  ores  monazife, 
(p.  206,)  and  pyrochlore,  (p.  208.) 

Thorite  is  a  hydrous  silicate  of  thoria.  It  is  a  black 
vitreous  mineral  resembling  gadolinite.  Gr  — 4*63.  From 
Norway. 

CLASS  VII.— METALS  AND  METALLIC  ORES. 

General  condition  of  Metals  and  Metallic  Ores  in  nature. — 
Metals  are  found  either  native,  or  mineralized  by  combination 
with  other  substances.  The  common  ores  are  compounds 
of  the  metals  with  oxygen,  sulphur,  arsenic,  carbonic  acid, 
or  silica.  For  example,  the  oxyds  and  carbonate  of  iron  are 
the  common  workable  iron  ores ;  sulphuret  of  lead  (called 
galena)  is  the  lead  ore  of  the  arts  ;  arsenical  cobalt  is  the 
principal  source  of  cobalt  and  arsenic. 

Only  a  few  of  the  metals  occur  native*  in  the  rocks.  Of 
these,  gold,  platinum,  palladium,  iridium,  and  rhodium,  are 
with  a  rare  exception,  found  only  native.  The  bismuth 

What  is  said  of  thoria  1  How  do  metals  occur  ?  What  are  ores  1 
Give  examples  from  ores  of  iron,  lead,  cobalt  ?  What  metals  occur 
principally  native  1 

*  By  native  is  understood  either  pure,  or  alloyed  with  other  metals,  ex- 
cluding those  metals,  like  arsenic  or  tellurium,  which  destroy  the  mal- 
leability of  the  metal  and  disguise  i;s  character.  Native  gold  is  much  of 
it  an  alloy  of  gold  and  silver.  But  a;iroteHitri1e,n.  compound  of  gold  and 
te!l.:rium  with  some  lead  and  silver,  is  properly  mineralized  gold. 


METALLIC    ORES.  203 

of  the  shops  is  obtained  from  native  bismuth.  Native  silver, 
7iative  mercury,  and  native  copper,  are  sometimes  abundant, 
but  are  far  from  being  the  main  sources  of  these  metals. 
The  other  native  metals  are  mineralogical  rarities.  Perhaps 
we  should  except  from  this  remark  native  iron,  which  con- 
stitutes large  meteoric  masses,  though  very  rarely  if  ever 
seen  of  terrestrial  origin. 

Their  associations  and  impurities. — The  ores  of  the 
metals  are  often  much  disguised  by  mixtures  with  one  an- 
other or  with  earthy  material.  Thus  a  large  part  of  the 
iron  ore  worked  in  England  and  this  country  is  so  mixed 
with  clay  or  silica,  that  its  real  character  might  not  be  sus- 
pected without  some  experience  in  ores. 

Occasionally  ores  contain  phosphate  of  iron  or  some  arsen- 
ical ores  or  certain  sulphurets,  scattered  through  them ;  and 
i  on  account  of  the  difficulty  of  separating  the  phosphorus,  sul- 
phur, or  arsenic,  the  ore  is  rendered  comparatively  useless. 
By  this  intimate  mixture  of  species,  tiie  difficulties  of  reducing 
ores  is  much  increased. 

When  different  ores  are  not  intimately  commingled,  they 
are  frequently  closely  disseminated  together  through  the 
rock.  We  find  ores  of  lead  and  zinc  often  thus  associated  ; 
also  of  cobalt  and  nickel ;  of  iron  and  manganese  ;  the  ores 
of  silver,  lead  and  copper,  and  often  cobalt  and  antimony ; 
platinum,  iridium,  palladium  and  rhodium. 

Position  in  rocks. — Metals  and  their  ores  occur  in  the 
rocks  in  different  ways  : 

1.  In  beds  or»layers  between  layers  of  rock,  as  some  iron 
ores ; 

2.  Disseminated  through  rocks  in  grains,  nests,  or  crystals, 
or  extended  masses,  as  is  the  case  with  iron  pyrites,  cinna- 

I  bar,  or  mercury  ore,  and  much  argillaceous  iron  ; 

3.  In  veins,  intersecting  different  rocks,  as  ores  of  tin, 
lead,  copper,  and  nearly  all  metallic  ores  ; 

4.  Very  frequently,  metallic  ores,  instead  of  occurring  in 
true  veins,  are  found  in  rocks  near  their  intersection  with  a 

,mass  or  dike  of  igneous  rock,  as  in  the  vicinity  of  a  por- 
iphyry  or  trap  dike.  This  is  the  case  with  much  of  the  cop. 
per  ore  in  Connecticut  and  Michigan,  as  well  as  with  much 


What  i?  siid  of  native  iron  1  How  are  ores  often  disguised  ]  Explain 
by  example.  How  do  they  occur  together  I  What  is  an  effect  of  this 
mixture  }  What  are  the  positions  of  ores  in  the  rocks  I 


204  METALS. 

silver  ore  and  mercury  in  South  America  and  elsewhere  ; 
and  often  the  igneous  rock  itself  contains  the  same  metals 
disseminated  through  it. 

Gangue. — The  rock  immediately  enveloping  the  ore  is 
called  the  gangue.  A  vein  often  consists  for  the  most  part 
of  the  rock  material  called  the  gangue  ;  and  the  ore  either 
intersects  the  gangue  in  a  continued  band,  or  more  com- 
monly, is  partly  disseminated  through  it  in  some  places,  and 
is  continuous  for  long  distances  in  others.  Often  a  good 
vein  gradually  loses  its  character,  the  metal  disappears,  and 
the  gangue  alone  is  left ;  but  by  following  on  for  some  dis- 
tance, it  will  often  resume  its  former  character. 

The  usual  gangue  in  metallic  veins  is  either  quartz,  calc 
spar,  or  heavy  spar ;  less  frequently  fluor  spar.  Calc  spar 
is  the  gangue  of  the  Rossie  lead  ore  ;  heavy  spar  of  much  of 
the  lead  ore  of  the  Mississippi  valley  ;  fluor  spar  in  some 
places  of  the  lead  of  Derbyshire,  England. 

Reduction  of  Ores. — In  the  reduction  of  an  ore,  the  object 
is  to  obtain  the  metal  in  a  pure  state.  It  is  necessary  for 
this  purpose  to  separate,  1,  the  gangue  ;  2,  the  impurities  or 
minerals  mixed  with  the  ore  ;  and  3,  the  ingredient  with 
which  the  ore  is  mineralized — as  the  sulphur,  for  example, 
in  the  common  ore  of  lead. 

1.  Much  of  the  gangue  will  be  separated  in  the  process  of 
mining  and  selecting  the  ore.  Another  portion  is  in  many 
cases  removed  by  pounding  the  ore  coarsely,  while  a  current 
of  water  is  made  to  pass  over  it;  the  water  carries  off  the 
lighter  earthy  matters  and  leaves  the  heavier  ore  behind. 
This  process  is  called  washing.  With  a  fusible  native  metal, 
as  bismuth,  it  is  only  necessary  to  heat  the  pounded  ore  injj 
crucibles,  and  the  metal  flows  out.  A  fusible  ore,  as  gray 
antimony,  is  separated  from  the  rock  in  the  same  manner. 
In  the  case  of  gold,  which  is  usually  in  disseminated  grains, 
mercury  is  mixed  with  the  pounded  rock  after  washing, 
which  unites  with  the  gold  ;  and  thus  the  gold  is  dissolved 
out  from  the  gangue  as  water  dissolves  a  salt ;  by  vapor- 
izing the  solvent,  mercury,  the  gold  is  afterwards  obtained. 

With  iron  ores,  there  is  no  special  effort  to  separate  the 
gangue  beyond  what  is  done  in  the  process  of  mining. 

What  is  the  gangue  1  What  is  said  of  the  ore  in  the  gangue  1  What 
are  the  common  kinds  of  gangue  ?  What  is  meant  by  the  reduction  of 
an  ore  ]  What  is  necessary^for  this  purpose  ?  How  is  the  gangue 
separated  ?  How  with  a  fu? ible  metal  or  ore  1  How  with  gold  7 


METALS.  205 

2.  The  separation  of  the  mineralizing  ingredients  when 
the  ore  is  pure,  is  sometimes  effected  by  heat  alone ;  thus  the 
common  ores  of  mercury  and  lead,  both  sulphurets,  will  give 
up  the  sulphur  in  part  when  heated.     In   most  cases,  some 
material  is  added  to  combine  with  the  mineralizing  ingre- 
dient and  carry  it  off;  as  when  certain  iron  ores  (oxyds  of 
iron)  are  heated  with  charcoal,  the  charcoal  takes  the  oxygen 
(forming  the  gas  carbonic  acid  which  escapes)  and  leaves 
the  iron  pure. 

3.  When  two  or  more  metals  are  mixed  in  the  ore,  one  is 
sometimes  removed  by  oxydation,  or  in  other  words,   it  is 
burnt  out.     Thus  lead  containing  silver,  is  heated  in  a  draft 
of  „  air ;  the  lead  unites  with  the  oxygen  of  the  air  and  forms 
an  earthy  slag,  while  the  silver,  which  is  not  thus  oxydated, 
remains  untouched.     Such  a  process,  carried  on  in  a  vessel 
of  bone-ashes,  or  some  material  of  the  kind,  which  will  ab- 
sorb the  oxyd  of  lead  formed,  is  called  cupdlation.     (See 
beyond  under  gold.)     Much  of  the  iron  in  the  ordinary  cop- 
per ore  (copper  pyrites)  is  removed  in  the  common  process 
of  reduction  in  England  by  repeated  fusions  and  stirring, 
while  exposed  to  a  draft  of  air. 

4.  When  there  are  impurities  present,  or  a  mixture  of  the 
gangue,  which  is  commonly  the  case,   a  material  is  sought 
for  which  will  form,  when  heated,  a  fusible  compound  with 
the  gangue  and  impurities  ;  and  this  material  is  called  a  flux. 
Most  iron  ores  are  associated  with  quartz  or  clay,  quartz  be- 
ing pure  silica,   and  clay  containing  75  per  cent,  of  silica. 
Common  limestone  readily  fuses   into  a  glass  with  silica, 
when  used  in  the  requisite  proportions,  and  hence  it  is  gen- 
erally employed  as  a  flux  in   iron  furnaces.     A  salt  of  soda 
or  potash  would  produce  the  same  result,  for  these  are  the 
ingredients   which   form  with  silica  common  glass.     The 
glass  formed  is  more  or  less  frothy,  and  is  called  slag  or  scoria. 

Before  reduction,  the  volatile  impurities  and  any  water 
present,  are  often  removed  by  a  process  called  roasting. 

The  processes  of  reducing  the  ordinary  metallic  ores  in 
the  arts  are  combinations  of  the  different  steps  here  pointed 
out.  There  are  other  chemical  methods  for  certain  cases, 
which  it  is  unnecessary  to  allude  to  in  this  place. 

How  is  the  mineralizing  ingredient  separated  in  some  cases?  How 
in  others  ?  Explain  by  example?.  How  in  cases  of  mixture.  Ex- 
plain the  process  of  cupeliation.  How  in  still  other  cases,  and  explain  the 
use  of  fluxes  by  an  example.  What  is  said  in  conclusion  of  the  pro- 
cesses of  reduction  ? 

18 


206  METALS. 

1.  2.  CERIUM  AND  YTTRIUM. 


Cerium  and  Yrttrium  are  not  used  in  the  arts.  The  spe- 
cies are  infusible  alone  before  the  blowpipe  or  only  in  the 
thinnest  splinters. 

YTTROCERITE. 

Massive,  of  a  violet-blue  color,  somewhat  resembling  a 
purple  fluor  spar;  sometimes  reddish-brown.  Opaque. 
Luster  glistening.  H  =  4 — 5.  Gr=3'4 — 3-5. 

Composition  :  fluoric  acid  25' 1,  lime  47-6,  oxyd  of  ceri- 
um, 18-2,  and  yttria  9'1  .  Infusible  alone  before  the  blow- 
pipe. 

Obs.  From  Finbo  and  Broddbo,  near  Fahlun  in  Swe- 
den, with  albite  and  topaz  in  quartz.  Also  from  Massachu- 
setts, probably  in  Worcester  county,  and  from  Amity,  Orange 
county,  N.  Y. 

Flucerine  and  Basic  Flucerine.  These  two  fluorids  of  cerium  have 
a  bright  yellow  or  yellowish-red  color.  Infusible  alone  in  the  blowpipe 
flame.  They  are  from  Sweden. 

Carbonate  of  Cerium  occurs  in  four-sided  plates  of  a  grayish-white 
color  at  Bastnas  in  Sweden.  Parisite  is  an  allied  species  occurring  in 
bipyramidal  dodecahedrons,  (fig.  65,  page  39,)  of  a  reddish-brown  color 
and  vitreous  fracture.  Cleavage  easy  parallel  to  the  base.  Gr=4'35. 
Infusible  alone.  Composition  :  carbonic  acid  23'5,protoxyds  of  cerium, 
lanthanum,  and  didymium  59.4,  lime  3'2,  fluorid  of  calcium  1T5,  water 
2'4.  From  New  Grenada. 

Cerium  Ochre  occurs  as  a  sulphur-yellow  coating  at  Bolton,  Mass. 
It  is  a  hydrated  yellow  oxyd  of  cerium,  containing  some  oxyd  of  ura- 
nium. 

MONAZITE. 

Monoclinate.  In  modified  oblique  rhombic  prisms ;  M  : 
M  =  93  10,  e  on  a=140°  40,  M  :  e=136D 
35'.  Perfect  and  brilliant  basal  cleavage.  Ob- 
served only  in  small  imbedded  crystals. 

Color  brown,  brownish-red  ;  subtransparent 
to  nearly  opaque.     Luster  vitreous  inclining 
vr-g-i^      to  resinous.    Brittle.    H=5.     Gr  =  4'8 — 5-1. 
Composition  :  oxyd  of  cerium  26'0,  oxyd  of 
lanthanum  23-4,  thoria  17-95,  phosphoric  acid  28'5,  with 

What  is  said  of  the  blowpipe  action  of  ores  of  cerium  and  yttrium  ? 
What  is  the  appearance  and  composition  of  yttrocerite  1  What  13 
monazite  ? 


CERIUM    AND    YTTKIUM    ORES.  207 

oxyd  of  tin  2*1,  protoxyd  of  manganese  1.9,  lime  1'7.  In- 
fusible or  nearly  so.  Decomposed  by  muriatic  acid,  evolving 
chlorine. 

Dif.  The  brilliant  easy  transverse  cleavage  distinguishes 
monazite  from  sphene. 

Obs.  Occurs  near  Slatoust,  Russia.  In  the  United 
States  it  is  found  in  small  brown  crystals,  disseminated  through 
a  rnica  slate  at  Norwich,  Conn. ;  also  at  Chester,  Conn.,  and 
Yorktown,  Westchester  county,  N.  Y. 

Cryptolite.  A  phosphate  of  the  oxyd  of  cerium  in  minute  prisms, 
(apparently  six-sided,)  found  with  the  apatite  of  Arendal,  Norway. 
Color  pale  wine  yellow.  Gr=4'6. 

ALLANITE. 

Monoclinate.  In  oblique  rhombic  prisms ;  M  :  M=128:). 
Cleavage  only  in  traces.  Also  massive  and  in  acicular  ag- 
gregations, the  needles  sometimes  a  foot  long. 

Color  pitch-brown,  brownish-black,  streak  greenish  or 
brownish-gray,  luster  pitchy  and  submetallic.  Opaque  or 
nearly  so.  Brittle.  H=5-5— 6.  Gr=3-3— 3-8. 

Varieties  and  Composition.  Allanite^  cerine,  and  orthite 
are  names  of  different  varieties  of  this  species.  The  last 
occurs  in  acicular  crystals  as  well  as  massive.  They  consist 
of  silica  and  alumina,  with  oxyds  of  iron,  cerium,  lanthanum, 
and  lime.  They  fuse  before  the  blowpipe  to  a  black  glassy 
globule  or  pearl. 

Dif.     Allanite  differs  from  garnet,  some  varieties  of  which 
it  resembles,  in  its  inferior  hardness,  and  colored  streak.  Gad- 
I  olinite  fuses  with  more  difficulty  and  glows  on  charcoal,  be- 
sides  gelatinizing  in  nitric  acid. 

Obs.  Allanite  was  first  brought  from  Greenland.  It  oc- 
I  curs  in  Norway,  Sweden,  and  the  Ural. 

In  the  United  States  it  has  been  found  in  large  crystals  in 
I  Allen's  vein,  Haddam  Conn. ;  at  Bolton,  Athol,  and  South 
Royalston,  Mass.  ;  at  Monroe,  Orange  county,  N.  Y. 

Pyrorthite.     This  appears  to  be  an  impure  orthite,  containing  some 
I  carbon,  in   consequence   of  which  it  burns   when  heated.     Hence  the 
naiiK'  from  the  Greek  pur,  fire,  and  orthite.     It  comes  from  near  Fah- 
;  lun,  Sweden. 

Cerite.  A  hydrated  silicate  of  cerium.  Color  between  clove-brown 
and  cherry-red.  Luster  adamantine.  Crystals  hexagonal.  From 
B;istniis,  Sweden. 

How  is  it  distinguished  from  fphene?  What  is  the  appearance  and 
}  composition  of  allanite  ?  what  are  iis  varieties  I 


208  METALS. 

Bodenite  is  a  cerium  ore,  resembling  orthite.  From  Boden  in 
Saxony. 

TYROCIILORE. 

In  small  octahedrons,  with  a  cleavage  parallel  to  the  faces 
1  of  the  octahedron  sometimes  dis- 

tinct. 

Color  yellow  to  brown.     Sub- 
transparent     to    opake.       Luster, 
vitreous    inclining     to     re-sinous. 
H=5.     Gr=3-8— 4-3. 

Composition :     essentially    co- 

Kimbic  acid,  with  oxyds  of  cerium,  thorium,  and  lime. 
tanic  acid   sometimes  replaces  part  of  the  columbic  acid. 
Fuses  with  very  great  difficulty  before  the  blowpipe. 

The  microlite  of  Prof.  Shepard  appears  to  be  pyrochlore. 
Dif.     The  color,  difficult  fusibility  and   colored    streak 
distinguish  this  species  from  others  crystallizing  in  octahe- 
drons.    It  is  much  softer  than  spinel. 

Obs.  Occurs  in  syenite  in  Norway,  and  also  in  Siberia. 
In  the  United  States  it  is  found  in  minute  octahedrons  at  the 
Chesterfield  albite  vein,  Mass. 

The  following  species  contain  yttrium  as  a  characteristic 
ingredient : — 

Xenotime  is  a  phosphate  of  yttria,  having  a  yellowish-brown  color, 
pale  brown  streak,  opaque,  and  resinous  in  luster.  Crystals  square  prisms, 
with  perfect  lateral  cleavage.  H=4 — 5.  Gr=4-G.  Infusible  alone 
before  the  blowpipe  ;  insoluble  in  acids.  From  Lindesnaes,  Norway. 

Gadolinite  has  a  black  or  greenish-black  color,  resinous  or  subvitre- 
ous  luster,  greenish-gray  streak.  Crystalline  form  an  oblique  rhombic, 
prism,  with  no  distinct  cleavage.  H=6'5 — 7.  Gr.=41— -4'4.  Con- 
sists mainly  of  silica,  yttria,  glucina,  and  protoxyd  of  iron,  with  also  the 
recently  discovered  oxyd  of  lanthanum.  From  Fahlun  and  Ytterby, 
Sweden  ;  also  from  Norway  and  Greenland. 

Fergitsonite  is  a  columbate  of  yttria,  crystallizing  in  secondaries  to  a 
square  prism.  Color  brownish-black ;  luster  dull,  but  brilliantly  vitre- 
ous on  a  surface  of  fracture.  Infusible  before  the  blowpipe  but  loses  its 
color.  From  Cape  Farewell,  Greenland. 

Yttro-columbite  is  a  columbate  of  yttria  containing  half  as  much 
yttria  as  the  preceding.  There  are  three  varieties,  the  black,  the  yel- 
low., and  the  brown  or  dark  colored.  They  are  infusible.  From  Ytter- 
by, Sweden,  and  at  Broddbo  and  Finbo,  near  Fahlun. 

Euxenile  is  a  columbate  of  yttria  with  some  titanic  acid  and  oxyd  of 
uranium.  Massive.  Color  brownish-black.  Streak  powder  reddish- 
brown.  Infusible.  From  Norway. 

What  is  the  oppearanee  and  composition  of  pyrochlore  ? 


UBANIUM    ORES.  209 

Tschevkinitc.  Resembles  gadolinite.  Color  velvet-black.  H=4 

4-5.  Gr=4'5— 4.6.  It  is  a  variety  of  allanite 

Polymignite  is  principally  a  titanate  of  zirconia,  yttria,  iron,  and  ce- 
rium. It  has  a  black  color,  a  brilliant  submetallic  luster  within,  a  dark 
brown  streak,  and  a  concheidal  fracture.  Generally  in  slender  striated 
crystals,  secondaries  to  a  rectangular  prism.  H=6'5.  Gr=4'7 — 4'9. 
From  Norway.  Also,  as  observed  by  Prof.  C.  U.  Shepard,  from  Bever- 
ly, Mass. 

Polycrase  is  near  polymignite.  Massive.  Color  black.  Streak 
grayish-brown.  Gr.=5  1.  With  orthite,  in  Sweden. 

Arkansite.  This  species,  from  the  Ozark  Mountains,  Arkansas,  oc- 
curs in  rather  large  modified  rhombic  prisms  ;  also  massive.  Color  iron 
black  or  steel  black.  Luster  shining.  Streak  dark  ash-gray.  H= 
7 — 7*5.  Gr.=3'S5..  Some  of  the  faces  tarnished  blue.  It  is  identi- 
cal vith  brorkite,  .  292, 

Schorlomite.  Black,  and  often  irised  tarnished.  Streak  grayish- 
black.  H=7— 75.  Gr=3'86.  Fuses  readily  on  charcoal.  Easily 
decomposed  by  the  acids,  and  gelatinizes.  Near  gadolinite.  From  the 
Ozark  Mountains,  Arkansas. 

3.    URANIUM. 

The  uranium  ores  have  a  specific  gravity  not  above  7,  and 
a  hardness  below  6.  The  ores  are  either  of  some  shade  of 
light  green  or  yellow,  or  they  are  dark  brown  or  black  and 
dull,  or  submetallic  without  a  metallic  luster  when  powdered. 
They  are  not  reduced  when  heated  with  carbonate  of  soda ; 
and  the  brown  or  black  species  fuse  with  difficulty  on  the 
edges  or  not  at  all. 

PITCHBLENDE. — Oxyd  of  Uranium. 

Massive  and  botryoidal.  Color  grayish,  brownish,  or  vel- 
vet-black. Luster  submetallic  or  dull.  Streak  powder 
black.  Opaque.  H=5'5.  Gr=6-47. 

Composition  :  79  to  87  per  cent,  of  protoxyd  of  uranium 
with  silica,  lead,  iron,  and  some  other  impurities.  Infusible 
alone  before  the  blowpipe,  but  forms  a  gray  scoria  with 
borax.  Dissolves  slowly  in  nitric  acid,  when  powdered. 

Obs.  Occurs  in  veins  with  ores  of  lead  and  silver  in  Sax- 
ony, Bohemia,  and  Hungary ;  also  in  the  tin  mines  of  Corn- 
wall, near  Redruth.  In  the  United  States,  at  Middletown 
and  Haddam,  Conn. 

Uranic  ochre  is  a  light  yellow  pulverulent  mineral,  be- 
coming orange  yellow  when  gently  heated.  It  is  believed 

What  is  said  of  the  ores  of  uranium  ?  Describe  pitchblende.  What 
is  its  composition  ? 

10* 


210  METALS. 

to  be  peroxyd  of  uranium,  sometimes  combined  with  carbon- 
ic acid.  Accompanies  pitchblende  in  Cornwall  and  in  Bo- 
hernia.  It  occurs  sparingly  in  a  yellow  powder  with  colum- 
bite  and  uranite  at  the  feldspar  quarry,  near  Middletown, 
Conn. 

Uses.  The  oxyds  of  uranium  are  used  in  painting  upon 
porcelain,  yielding  a  fine  orange  in  the  enameling  fire,  and 
a  black  color  in  that  in  which  the  porcelain  is  baked. 

Coracite  (Le  Conte.)  An  ore  resembling  pitchblende  but  containing 
alumina  in  place  of  part  of  the  oxyd  of  uranium.  Occurs  massive,  with 
a  resinous  luster.  H=4'5.  Gr=4'38.  From  the  north  shore  of  Lake 
Superior,  in  a  vein  2  inches  wide,  near  the  junction  of  trap  and  syenite. 

URANITE. 

Dimetric.  In  short  square  prisms,  thinly  foliated  parallel 
to  the  base,  almost  like  mica  ;  laminae  brittle  and  not  flex- 
ible. 

Color  bright  clear  yellow  and  green ;  streak  a  little  pa- 
ler. Luster  of  laminae  pearly.  Transparent  to  subtrans- 
lucent.  H  =  2— 2-5.  Gr=3— 3-6. 

Composition.  There  are  two  ores  here  included,  the  yel- 
low one  containing  phosphoric  acid  15,  oxyd  of  uranium  64, 
and  lime  6,  with  water  15 ;  the  other  of  a  green  color, 
(sometimes  called  chalcolite,)  containing  oxyd  of  copper  in 
place  of  lime.  They  fuse  before  the  blowpipe  to  a  blackish 
mass,  and  the  green  variety  colors  the  flame  green. 

Dif.  The  micaceous  structure  connected  with  the  light 
color  is  a  striking  character.  The  folia  of  mica  are  not 
brittle  like  those  of  uranite. 

Obs.  Occurs  with  uranium,  silver  and  tin  ores.  It  is 
found  at  St.  Symphorien,  near  Autun,  and  also  near  Limoges, 
and  in  the  Saxon  and  Bohemian  mines.  Cornwall  affords 
splendid  crystallizations  of  the  green  variety. 

Found  sparingly  at  Middletown,  Conn.,  and  Chesterfield, 
Mass.,  of  a  yellow  color. 

Samarskite  (formerly  named  uranotantalite  and  yttro-ilmenite)  is  a 
compound  of  oxyd  of  uranium  with  niobic  and  tungstic  acids,  from 
Miask  in  the  Ural.  It  is  of  a  dark  brown  color  and  submetallic  luster. 
H=5-5.  Gr=5-4— 5-7. 

Johannite  or  uranvitriol  is  a  sulphate  of  uranium.  It  has  a  fine  em- 
erald-green color,  and  a  bitter  taste.  From  Bohemia. 

What  are  the  uses  of  the  oxyds  of  uranium  ?  What  is  the  color  and 
structure  of  uranite  1  its  composition  1  How  is  it  distinguished  from 
other  species  ? 


IRON    ORES.  211 

4.    IRON. 

Iron  occurs  native  or  alloyed  with  nickel  in  meteoric  iron, 
ts  most  abundant  ores  are  the  oxyds  and  sulphurets.  It  is 
folso  found  combined  with  other  metals  and  with  silica  and 
[carbonic  and  other  acids.  Its  ores  are  widely  disseminated. 
They  are  the  ordinary  coloring  ingredients  of  soils  and  many 
rocks,  tinging  them  red,  yellow,  dull  green,  brown  and  black. 

The  ores  have  a  specific  gravity  below  8,  and  the  ordina- 
ry workable  ores  seldom  exceed  5.  Many  of  them  are  in- 
fusible before  the  blowpipe,  and  a  great  part  become  attract- 
able  by  the  magnet  after  heating,  when  not  so  before.  When 
undisguised  by  other  metals  they  afford,  with  borax,  in  the 
inner  flame,  a  bottle-green  glass.  By  their  difficult  fusibil- 
ity, the  species  with  a  metallic  luster  are  distinguished  from 
ores  of  silver  and  copper,  and  also  more  decidedly  from  these 
and  other  ores  by  blowpipe  reaction  and  reduction. 

NATIVE    IRON. 

Monometric.  In  regular  octahedrons  ;  cleavage  parallel 
10  the  faces  of  the  octahedron.  Usually  massive,  with  a 
more  or  less  fine  granular  structure. 

Color  and  streak  iron-gray.  Fracture  hackley.  Malleable 
and  ductile,  H=4'5.  Gr=7-3 — 7.8.  Acts  strongly  on 
the  magnet. 

Obs.  Native  iron,  as  it  occurs  in  meteorites,  is  usually  al- 
loyed with  nickel  and  other  metals.  Whether  terrestrial  na- 
tive iron  has  been  observed,  is  a  question  of  some  doubt.  A 
mass  from  Canaan,  Conn.,  has  been  reported  as  of  this 
character,  and  it  is  said  to  have  formed  a  plate  or  vein  two 
inches  thick,  attached  to  a  mass  of  mica  slate.  Steinbach 
and  Eibenstock  in  Saxony,  and  the  mine  of  Hackenberg 
hav-fi  been  mentioned  as  foreign  localities. 

Meteoric  iron  occurs  in  nearly  all  meteorites,  and  al- 
most wholly  constitutes  a  large  part  of  those  that  have  been 
discovered.  A  mass  weighing  1635  pounds,  is  now  in  tho 
cabinet  of  Yale  College  ;  it  came  from  Texas.  It  contains 

What  is  said  of  the  mode  of  occurrence  of  iron  ?  What  characters 
of  its  ores  are  mentioned  ?  What  is  the  crystallization  of  iron  ?  its 
hardness,  gravity, and  other  characters?  How  does  it  occur  native  1 
What  is  said  of  meteoric  iron  ? 


212  METALS. 

90  to  92  per  cent,  of  iron,  and  8  to  10  per  cent,  of  nickel, 
the  alloy  not  being  uniform  throughout.  Meteoric  iron  often 
has  a  very  broad  crystalline  structure,  long  lines  and  triangu- 
lar figures  being  developed  by  putting  nitric  acid  on  a  polish- 
ed  surface.  The  coarseness  of  this  structure  differs  in  dif- 
.  ferent  meteorites,  and  serves  to  distinguish  specimens  not 
identical  in  origin.  The  Texas  iron  is  remarkable  for  the 
large  size  of  the  crystallization. 

The  most  remarkable  masses  of  meteoric  iron  occur  in 
the  district  of  Chaco-Gualamba  in  South  America,  where 
there  is  one  whose  weight  is  estimated  at  30,000  pounds. 
The  large  Pallas  meteorite  weighed  originally  1600 pounds; 
it  contains  imbedded  crystals  of  chrysolite. 

Besides  nickel,  which  sometimes  amounts  nearly  to  15 
per  cent.,  meteoric  iron  often  contains  a  small  per-centage 
of  cobalt,  tin,  copper,  and  manganese  ;  and  frequently  no- 
dules  of  magnetic  iron  pyrites  are  imbedded  in  the  mass. 
Chlorine  has  been  detected  in  some  specimens,  bv  Dr.  C. 
T.  Jackson. 

Meteoric  iron  is  perfectly  malleable,  and  may  be  worked 
like  manufactured  iron.  The  nickel  diminishes  much  its 
tendency  to  rust. 

IRON  PYRITES. — Bisulphuret  of  Iron. 

Monometric.     Usually  in  cubes  (fig.  1)  simple  or  modifi- 
1  2  ^3  4 


ed,  (2,  4,)  or  in  pentagonal  dodecahedrons  (3)  ;  also  in  octa- 
hedrons. Faces  of  cubes  often  striated  as  in  figure  1.  Oc- 
curs also  in  imitative  shapes,  and  massive. 

Color  bronze-yellow  ;  streak  brownish-black.  Luster  of 

crystals  often  splendent  metallic.  Brittle.  H=6 6-5. 

Gr=4-8— 5-1.  Strikes  fire  with  steel. 

Composition:  iron  45-74,  sulphur  54-26.  Before  the 
blowpipe,  gives  off  sulphur  and  ultimately  affords  a  globule 
attractable  by  the  magne* 

What  is  the  crystallization  of  iron  pyrites  ?  its  color  and  other  char- 
acters? its  composition  ? 


OR:ES, 

Pyrites  sometimes  contains  a  minute  quantity  of  gold,  and 
is  then  called  auriferous  pyrites. 

Dif.  Distinguished  from  copper  pyrites  in  being  too  hard 
to  he  cut  by  a  knife,  and  also  hi  its  paler  color.  The  dres 
of  silver,  ai  all  approaching  pyrites,  instead  of  having  its 
pale  bronze-yellow  color,  are  steel-gray  or  nearly  black ; 
und  besides,  they  are  easily  cut  with  a  knife  and  quite  fusi- 
t>le.  Gold  is  sectile  and  malleable  ;  and  besides,  it  does  not 
<ii\  e  off  a  sulphur  odor  before  the  blowpipe,  like  pyrites. 

Ob&.  Iron  pyrites  is  one  of  the  most  common  ores  on  the 
globe.  It  occurs  in  rocks  of  all  ages.  Cornwall,  Elba, 
Piedmont,  Sweden,  Brazil,  and  Peru,  have  afforded  magnifi- 
cent crystals.  Alston  Moor,  Derbyshire,  Kongsberg  in  Nor- 
way, are  well  known  localities.  It  has  also  been  observed 
ia  the  Vesuvian  lavas, 

In  the  United  States,  the  localities  are  numerous.  Fine 
crystals  have  been  met  with  at  Rossie,  N.  Y.  ;  also  in  New 
York  state  at  Scoharie,  at  Johnsburg  and  Chester,  Warren 
county;  at  Champion  and  near  Oxbow,  in  Jefferson  county; 
at  Warwick  and  Deerpark,  Orange  county.  In  Vermont, 
crystals  occur  at  Shoreham ;  in  Massachusetts,  at  Heath, 
liarre,  and  Boxborough  ;  in  Maine,  at  Corinna,  Peru,  Wa- 
terviile  and  Farmington  ;  in  Connecticut,  at  Monroe,  Orange, 
Milford  and  Stafford  ;  in  Pennsylvania,  at  Little  Britain, 
Lancaster  county.  Massive  pyrites  occurs  in  Connecticut  at 
Colchester,  Ashford,  Tolland,  Stafford,  and  Union ;  in  Mas- 
sachusetts, at  Hawley  and  Hubbardston  ;  in  Maine,  at  Bing- 
ham,  Brooksville,  and  Jewell's  Island;  in  New  Hampshire, 
at  Unify ;  in  Vermont,  at  Stratford,  where  there  is  a  vein  in 
mica  slate  four  rods  wide,  and  also  abundantly  at  Woodbury, 
and  other  places;  in  New  York,  in  Franklin,  Putnam  and 
Orange  counties,  and  elsewhere  ;  in  Maryland,  abundant  and 
worked  at  Cape  Sable. 

Uses.  This  species  is  of  the  highest  importance  in  the 
ail*,  although  not  affording  good  iron  on  account  of  the  diffi- 
culty of  separating  entirely  the  sulphur.  It  affords  the 
greater  part  of  the  sulphate  of  iron  (green  vitriol  or  copper- 
as) and  sulphuric  acid  (oil  of  vitriol)  of  commerce,  and  alse 
21  considerable  portion  of  the  sulphur  and  alum.  The  py- 

How  is  iron  pyrites  disdnssiished  from  copper  pyrites  ?  from  silver 
ores?  from  gold  ?     What  is  said  of  the  occurrence  of  pyrites  1     Why 
ixs  not  this  ore  afford  good  iron  1     What  are  its  uses  ?     How  is  vitriol 
Vi'inpd  from  it  I 


214  METALS. 

rites  is  sometimes  heated  in  clay  retorts,  by  which  about  17 
per  cent,  of  sulphur  is  distilled  over  and  collected.  The  ore 
is  then  thrown  out  into  heaps,  exposed  to  the  atmosphere, 
when  a  change  ensues,  by  which  the  remaining  sulphur  and 
iron  become  sulphuric  acid  and  oxyd  of  iron,  and  form  sulphate 
of  iron  or  copperas.*  The  material  is  lixivated,  and  par- 
tially evaporated,  preparatory  to  its  being  run  off  into  vats 
or  troughs  to  crystallize.  In  other  instances^  the  ore  is 
coarsely  broken  up  and  piled  in  heaps  and  moistened.  Fuel 
is  sometimes  used  to  commence  the  process,  which  after- 
wards the  heat  generated  continues.  Decomposition  takes 
place  as  before,  with  the  same  result*  At  Stratford,  Ver- 
mont, about  1000  tons  of  copperas  have  been  produced  an- 
nually, valued  at  2  cents  a  pound,  or  $40,000.  The  quanti- 
ty manufactured  might  easily  be  much  increased.  The  py- 
rites of  Cape  Sable,  Maryland,  also  affords  large  quantities 
of  copperas.  The  lixivated  liquid  is  often  employed  in  Ger- 
many for  the  production  of  sulphuric  acid  ;  at  a  red  heat,  the 
acid  passes  off,  leaving  behind  a  red  oxyd  of  ironr  which  is 
called  colcothar.  Cabinet  specimens  of  pyrites,  especially 
granular  or  amorphous  masses,  often  undergo  a  spontaneous 
change  to  copperas,  particularly  when  the  atmosphere  is  moist. 

The  name  pyrites  is  from  the  Greek  pur,  fire,  because,  as 
Pliny  states,  "  there  was  much  fire  in  it,"  alluding  to  its  strik- 
ing fire  with  steel.  This  ore  is  the  mundic  of  miners. 

White  iron  pyrites.  This  ore  has  the  same  composition,  as  common 
iron  pyrites,  but  crystallizes  in  secondaries  to  a  right  rhombic  prism  ; 
M  :  M=106°  36'.  The  color  is  a  little  paler  than  that  of  common  py- 
rites, and  it  is  more  liable  to  decomposition  ;  hardness  the  same  ;  spe- 
cific gravity  4' 6 — 4- 85.  Radiated  pyrites.,  hepatic  pyrites,  cocks- 
comb pyrites,  (alluding  t0  its  crested  shapes,)  and  spear  pyrites  are 
names  of  some  of  its  varieties.  It  occurs  in  crystals  at  Warwick  and 
Phillipstown,  N.  Y.  Massive  varieties  are  met  with  at  Cummin gton> 
Mass.  ;  Monroe,  Trumbull,  and  East  Haddam,.  Conn. :  and  at  Huvcr- 
hill,  N.  H. 

MAGNETIC  PYRITES. — Sulphuret  of  Iron. 
Hexagonal.     Occurs  occasionally  in    hexagonal  prisms, 
which  are  often  tabular  ;  generally  massive. 

Color  between  bronze-yellow  and  copper-red  ;  streak  dark 

How  is  sulphuric  acid  obtaine1?  and  what  is  colcothar  1  What  is  the 
origin  of  the  name  pyrites]  What  is  the  erystalrkatieft  and  appear- 
ance of  magnetic  pyrites? 

*  This  change  consists  in  the  unioo.  of  oxygen  with  the  sulphur  ami 
iron. 


IRON    ORES*  215 

grayish-black.  Brittle.  H=3«5 — 4-5.  Gr=4*6 — 4-65. 
Slightly  attracted  by  the  magnet.  Liable  to  speedy  tarnish. 

Composition  :  sulphur  40'4,  iron  59'6.  Before  the  blow- 
pipe on  charcoal  in  the  outer  flame  it  is  converted  into  a  glo- 
bule of  red  oxyd  of  iron.  In  the  inner  flame  it  fuses  and 
glows,  and  affords  a  black  globule  which  is  magnetic,  and  has 
a  yellowish  color  on  a  surface  of  fracture. 

Dif.  Its  inferior  hardness  and  shade  of  color,  and  its 
magnetic  quality  distinguish  it  from  common  iron  pyrites ;  and 
its  paleness  of  color  from  copper  pyrites.  It  differs  from  the 
cobalt  and  nickel  ores  in  affording  a  magnetic  globule  before 
the  blowpipe. 

Obs.  Crystallized  specimens  have  been  found  at  Kongs- 
berg  in  Norway,  and  at  Andreasberg  in  the  Hartz.  The 
massive  variety  is  found  in  Cornwall,  Saxony,  Siberia,  and 
the  Hartz ;  also  at  Vesuvius  and  in  meteoric  stones. 

In  the  United  States,  it  is  met  with  at  Trumbull  and  Mon- 
roe, New  Fairfield,  and  Litchfield,  Conn. ;  at  Strafford  and 
(Shrewsbury,  Vt. ;  at  Corinth,  New  Hampshire ;  and  in 
(many  parts  of  Massachusetts  and  New  York.  This  ore  at 
Litchfield  is  quite  abundant. 

Uses.     Same  as  for  common  pyrites* 

MISPICKEL. — Arsenical  Iron  Pyrites. 

Trimetric.     In  rhombic  prisms,  with  cleavage  parallel  to 
the  faces  M  ;  M  :  M=lll°  40'  to  112°.     Crystals 
isomethnes   elongated   horizontally,    producing    a 
rhombic  prism  ("a  :  'a)  of  100°  nearly,  with  M  and 
M  the  end  planes.     Occurs  also  massive. 

Color  silver-white  ;  streak  dark  grayish-black. 
[Luster  shining.     Brittle.     H=5*5 — 6.    Gr=6'l. 

Composition :  iron  36*0,  arsenic  42*9,  sulphur  21*1.  A 
'cobaltic  variety  contains  4  to  9  per  cent,  of  cobalt  in  place 
of  pail  of  the  iron.  The  Danaite  of  New  Hampshire,  con- 
sists of  iron  32'9,  arsenic  41 '4,  sulphur  17'8,  cobalt  6'5. 
Affords  arsenical  fumes  before  the  blowpipe,  and  a  globule 
lof  sulphuret  of  iron  which  is  attracted  by  the  magnet.  It 
'gives  fire  with  a  steel  and  emits  a  garlic  odor. 

Dif.     Resembles  arsenical  cobalt ;  but  is  much  harder, 

What  is  the  constitution  of  magnetic  pyrites  1  How  is  it  distinguish- 
ed from  common  iron  pyrites  1  how  from  copper  pyrites  ?  from  cobalt 
and  nickel  ores.  For  what  is  it  used  ?  What  is  the  form  and  appear- 
jance  of  mispickel  ? 


216  METALS, 

it  giving  fire  with  steel ;  it  differs  also  in  yielding-  a  mag- 
netic globule  before  the  blowpipe  and  in  not  affording  the 
reaction  of  cobalt  with  the  Suxes. 

Obs.  Mispickel  is  found  mostly  in  primitive  regions,  and 
is  commonly  associated  with  ores  of  silver,  lead,  iron,  or 
copper.  It  is  abundant  at  Freiberg,  Munzig,  and  elsewhere 
in  Europe,  and  also  in  Cornwall,  England. 

It  occurs  in  crystals  in  New  Hampshire,  at  Franconia, 
Jackson,  and  Haverhill ;  in  Maine,  at  Blue  Hill,  Comma, 
Newfield,  and  Thomaston  ;  in  Vermont,  at  Waterbury  ;  fn 
Massachusetts,  massive  at  Worcester  and  Sterling ;  in  Con- 
necticut, at  Chatham,  Derby,  and  Monroe  ;  in  New  Jersey, 
at  Franklin  ;  in  New  York,  in  Lewis,  Essex  county,  and  near 
Edenvflle  and  elsewhere  in  Orange  county ;  in  Kent,  Put- 
nam county. 

Lcucopyrite.  This  is  the  name  of  an  arsenical  iron,  eontainining  no 
sulphur,  or  but  few  per  cent.  It  resembles  the  preceding  in  color  and 
in  its  crystals  ;  M  :  M=122°  26'.  It  has  less  hardness  and  higher  spe- 
cific gravity.  H=5— 5'5.  Gr=7'2— 7'4.  Contains  iron  32-4,  ar- 
senic 65*9,  with  some  sulphur.  From  StyriarSiiesia,aml  Carinthia,  A 
crystal  weighing  two  or  three  ounces  has  been  found  in  Bedford1  county, 
Penn.  ;  and  in  Randolph  county,  N.  C.,  a  mass  was  found  weighing  two 
pounds. 

MAGNETIC  IKON  ORE. — Octahedral  Iron  Ore, 

Monometric.     Often  in  octahedrons  and  dodecahedrons, 
Cleavage  octahedral  ;  sometimes 
distinct.     Also   granularly   mas- 
sive 

Color  iron-black.  Streak  black. 
Brittle.      H=  5-5— 6-5.      Gr= 
5*0 — 5*1.     Strongly  attracted  by 
the  magnet,  and  sometimes  having  polarity. 

Composition:  peroxyd  of  iron  69,  protoxyd  of  iron  31  ;  or 
iron  71 '8,  oxygen  28 '2.  Infusible  before  the  blowpipe. 
Yields  a  bottle-green  glass  when  fused  with  borax  in  the 
inner  flame. 

Dif.  The  black  streak  and  magnetic  properties  distin- 
guish this  species  from  the  following. 

What  are  the  constituents  of  mispickel  1  What  is  the  effect  before 
the  blowpipe  1  How  does  it  differ  from  arsenical  cobalt  ?  What  is 
the  crystallization  of  magnetic  iron  ?  its  other  physical  characters  1  its 
composition  1  What  is  the  action  of  magnetic  iron  before  the  blowpipfe  1 
How  is  it  distinguished  from  specular  iron  ] 


IBON   ORES.  217 

Obs.  'Magnetic  iron  ore  occurs  in  extensive  beds,  and 
also  in  disseminated  crystals.  It  is  met  with  in  granite, 
gneiss,  mica  slate,  clay  slate,  syenite,  hornblende,  and  chlo- 
rite slate  ;  and  also  sometimes  in  limestone. 

The  beds  at  Arendal,  and  nearly  all  the  Swedish  iron  ore, 
consist  of  massive  magnetic  iron.  At  Dannemora  and  the 
Taberg  in  Southern  Sweden,  and  also  in  Lapland  at  Kurun- 
avara  and  Gelivara,  there  are  mountains  composed  of  it. 

In  the  United  States,  extensive  beds  occur  in  Warren, 
Essex,  and  Clinton  counties,  N.  Y.  ;  also  in  Orange,  Putnam, 
Saratoga,  and  Herkimer  counties ;  at  Mount  Desert  and 
Marshall's  Island,  Maine  ;  in  Somerset,  Vermont ;  in  Bcr- 
nardstown  and  Hawley,  Massachusetts ;  at  Franconia,  Lis- 
bon, and  Winchester,  New  Hampshire.  The  mountainous 
districts  of  New  Jersey  and  Pennsylvania  afford  this  ore,  and 
also  the  eastern  side  of  Willis  mountain  in  Buckingham 
county,  Virginia.  Crystals  occur  in  New  Hampshire,  at 
Franconia  in  epidote  ;  also  at  Swanzey,  (near  Keene,)  Unity, 
and  Jackson ;  in  Vermont,  at  Marlboro',  Bridgewater  and 
Troy,  in  chlorite  slate  ;  in  Connecticut,  at  Haddam  ;  in  Maine, 
at  Raymond,  Davis's  Hill,  in  an  epidotic  rock  ;  in  New  York, 
at  Warwick,  Orange  county,  and  also  at  O'Neil  mine ;  in 
New  Jersey,  at  Hamburgh,  near  the  Franklin  furnace  ;  in 
Maryland,  at  Deer  Creek  ;  in  Pennsylvania,  at  Morgantown, 
Berks  county ;  also  in  the  south  part  of  Chester  county. 

Masses  of  this  ore  in  a  state  of  magnetic  polarity,  consti- 
tute what  is  called  lodestone  or  native  magnets.  They  are 
met  with  in  many  beds  of  the  ore.  Siberia  and  the  Hartz 
have  afforded  fine  specimens ;  also  the  island  of  Elba.  They 
also  occur  at  Marshall's  Island,  Maine  ;  also  near  Providence, 
'  Rhode  Island.  The  lodestone  is  called  magnes  by  Pliny, 
1  from  the  name  of  the  country,  Magnesia,  (a  province  of  an- 
cient Lydia,)  where  it  was  found ;  and  it  hence  gave  the 
terms  magnet  and  magnetism  to  science. 

Uses.  No  ore  of  iron  is  more  generally  diffused  than 
the  magnetic  ore,  and  none  is  superior  for  the  manufacture 

•  of  iron.     The  ore  after  pounding  may  be  separated  from  im- 

•  purities  by  means  of  a  magnet ;  and  machines  are  in  use  in 
northern  New  York  and  elsewhere,  for  cleaning  the  ore  on 
a  large  scale  for  furnaces. 

How  does  magnetic  iron  occur  ?  What  are  its  uses  ?  What  is  said 
of  lodestone  t 

19 


213 


SPECULAR  IRON  ORE.  —  Peroxyd  of  Iron* 
Rhombokedral.     In  complex  modifications  of  a 


dron  of  85°  58' ;  crystals  occasionally  thin  tabular.  Cleavage? 
usually  indistinct.  Often  massive  granular  ;,  sometime* 
lamellar  or  micaceous.  Also  pulverulent  and  earthy. 

Color  dark  steel-gray  or  iron-black,  and  often  when  crys- 
tallized having  a  highly  splendent  luster ;  streak-powder 
cherry -red  or  reddish-brown.  The  metallic  varieties  pass* 
into  an  eartny  ore  of  a  red  color,  having  none  of  the  external 
characters  of  the  crystals,  but  perfectly  correspond  nig  to  them 
when  they  are  pulverized,  the  powder  they  yield  being  of  a 
deep  red  color,  and  earthy  or  without  luster.  Gr=4.5 — • 
5*3.  Hardness  of  crystals  5*5— 6-5,  Sometimes  slightly 
attracted  by  the  magnet. 

Varieties  and  Composition. 

Specular  iron.  Specimens  having  a  perfectly  metallic 
luster. 

Micaceous  iron.     Specular  iron,  with  a  foliated  structure* 

Red  hematite.  Submetallic,  or  unmetallic,  and  of  a  brown- 
ish-red color* 

Red  ocher.     Soft  and  earthy,  and  often  containing  clay. 

Red  chalk.  More  firm  and  compact  than  red  ocher,  and 
of  a  fine  texture. 

Jaspery  clay  iron.  A  bard  impure  ore,  containing  clay,, 
and  having  a  brownish-red  jaspery  look  and  compactness. 

Clay  iron  stone.  The  same  as  the  last,  the  color  and  ap- 
pearance less  like  jasper. 

This  is  one  variety  of  what  is  called  "clay  iron  stone. " 
Much  of  it  belongs  to  the  following  species,  and  a  large 
part  also  is  spathic  iron,  as  is  the  case  with  that  of  the  Eng- 
lish coal  measures. 

Lenticular  argillaceous  ore.  A  red  ore,  consisting  of 
small  flattened  grains,  something  like  an  oolite. 

Oligiste  iron,  iron  glance,  and  rhombohedral  iron  ore,  are 
other  names  of  the  species  specular  iron. 

What  is  the  crystallization  of  specular  iron  ?  What  are  its  physical 
characters  ?  Describe  the  varieties. 


TROT*    ORES. 

of  the  pure  ore  :  iron  69*34,  oxygen  30'66. 
Tho  varieties  without  a  perfect  metallic  luster  often  contain 
more  or  less  clay  or  sand.  Before  the  blowpipe  alone  infu- 
sible ;  with  borax  in  the  inner  fiame  gives  a  green  glass, 
,and  a  yellow  glass  in  the  outer  flame- 

Dif.  This  ore  is  distinguished  from  magnetic  iron  ore 
£>y  its  red  -powder ;  and  from  any  silver  or  copper  ores  by 
ats  hardness  and  infusibility.  The  word  hematite,  from  the 
Greek  kaima,  blood,  alludes  to  the  color  of  the  powder. 

Obs.  This  ore  occurs  in  "both  crystalline  and  stratified 
s-ocks,  and  is  of -all  ages.  The  more  extensive  beds  of  pure 
ore  abound  in  the  piimary  rocks;  while  the  argillaceous 
varieties  occur  in  stratified  rooks,  being  often  abundant  in 
«coal  regions  and  other -strata.  Crystallized  specimens  occur 
also  in  some  lavas. 

Splendid  c^stallizations  of  this  ore  come  from  Elba,  whose 
t>eds  were  known  to  the  Romans;  also  from  St.  Gothard; 
Arendal,  Norway  ;  Langbanshyttan,  Sweden  ;  Lorraine  and 
Dauphiuy.  Etna  and  Vesuvius  afford  handsome  specimens. 

In  the  United  States,  this  is  an  abundant  ore.  The  two 
iron  mountains  of  Missouri,  situated  90  miles  south  of  St. 
Louis,  consist  mainly  of  this  ore,  piled  "in  masses  of  all 
sizes  from  a  pigeon  s  egg  to  a  middle  size  church."  One  of 
••them  is  150  feet  high,  and  the  other,  the  "  Pilot  knob,"  is  700 
feet.  Both  the  massive  and  micaceous  varieties  occur  there 
together  with  red  ochreous  ore.  Large  beds  of  specular 
iron  have  been  explored  in  St.  Lawrence  aad  Jefferson 
.counties,  N.  Y. ;  Plymouth,  Bartlett  and  elsewhere  in  New 
Hampshire  ;  Woodstock  and  Aroostock,  Maine,  .and  Liberty, 
Maryland,  are  other  localities ;  also  the  Blue  Ridge,  in  the 
western  part  of  Orange  county,  Va.  The  micaceous  variety 
occurs  at  Hawley,  Mass.,  Piermont,  N.  H.,  and  in  Stafford 
^county,  Va.  Lenticular  argillaceous  ore  is  abundant  in 
Oneida,  Herkimer,  iMadison,  and  Wayne  counties,  N.  Y.,  con- 
stituting one  -or  two  beds  12  to  2Q  inches  thick  in  a  compact 
•sandstone ;  it  contains  50  per  cent  of  oxyd  of  iron,  with 
^about  25  of  carbonate  of  lime,  and  more  or  less  magnesia  and 
<clay.  The  coal  region  of  Pennsylvania  affords  -abundantly 
the  clay  iron  ores,  but  they  are  mostly  the  argillaceous  carbo- 
nate of  iron  or  hematite. 

What  is  the. composition  of  specular  iron  1  What  are  its  distinguish- 
ing characters?  What  is  its  mode  .of  occurrence  1  What  is  said  of 
•Soic  icon  mountains  of  -Missouri  J? 


220  METALS. 

Uses.  Valuable  as  an  iron  ore,  though  less  easily  worked 
when  pure  and  metallic  than  the  magnetic  and  hematitic 
©res.  Pulverized  red  hematite  is  used  for  polishing  metals, 
Red  chalk  is  a  well  known  material  for  red  pencils. 

BROWN  IRON  ORE, — Brown  Hematite, 

Usually  massive,  and  often  with  a  smooth  botryoicFal  or 
stalactitic  surface,  having  a  compact  fibrous  structure  with  in. 
Also  earthy. 

Color  dark  brown  to  ocher-yellow ;  streak  yellowish- 
brown  to  dull  yellow.  Luster  sometimes  submetallic  ;  often 
dull  and  earthy;  on  a  surface  of  fracture  frequently  silky. 
H=5— 5-5.  Gr=3-6— 4. 

Varieties  and  Composition.  The  following  are  the  princi- 
pal varieties : 

Brown  hematite.  The  botiyoidal,  stalactttic  and  associated 
compact  oa*e. 

Brown  ocher,  Yellow  acher.  Earthy  ochreous  varieties, 
of  a  brown  or  yellow  color. 

Brown  and  yellow  clay  iron  stone.  Impure  ©re,  hard  and 
compact,  of  a  brown  or  yellow  color. 

Bog  iron  ore.  A  loose  earthy  ore  of  a  brownish-black 
color,  occurring,  in  low  grounds. 

Composition when  pure  :  peroxyd  of  iron  85*3,  (seven-tenths' 
©f  which  is  pure  iron,)  and  water  14*7 ;  or  it  rs  a  Tiydrous 
peroxyd  of  iron,  containing  when  pure  about  two-thirds  its 
weight  of  pure  iron.  Before  the  blowpipe,  blackens  and  be- 
comes magnetic.  Gives  with  borax,  in  the  inner  flame  a 
green  glass. 

Dif.  This  is  a  much  softer  ore  than  either  of  the  two  pre- 
ceding, and.  is  peculiar  in  its  frequent  stalactitic  forms,  and 
in  its  affording  water  when  heated  in  a  glass  tube. 

Obs.  Occurs  connected  with  rocks  of  all  ages,  but  ap- 
pears, as  shown  by  the  stalactitic  and  other  forms,  to  have 
resulted  in  all  cases  from  the  decomposition  of  other  iron  ores, 
probably  the  swlphuret. 

This  is  an  abundant  ore  in  the  United  States.  The  fol- 
lowing are  a  few  of  its  localities.  Extensive  beds  exist  at 
Salisbury  and  Kent,  Conn.,  in  mica  slate;  aU-oiii  the  neigh- 


What  is  said  of  the  uses  of  specular  iron  ?  What  is  the  appearance 
of  brown  iron  ore  ?  its  composition  ?  Describe  its  varie  ies.  Wku 
are  distinguishing  characters  I  II&w  dws  this  ore  occur  I 


OITEB. 

feoring  towns  of  Beekrnan,  Fishkill,  Dover,  and  Amenia,  N. 
Y.  ;  also  in  a  similar  situation  north,  at  Richmond  and  Lenox, 
Mass.  $  alse  at  Bennington,  Monktou,  Pittsford,  Putney,  and 
Ripton,  Vermont.  Large  beds  are  found  in  Pennsylvania, 
the  Carolinas,  near  the  Missouri  iron  mountains,  and  also  in. 
Tennessee,  Iowa  and  Wisconsin, 

Uses.  This  is  one  of  the  most  valuable  ores  of  iron.  It 
is  also  pulverised  and  used  for  polishing  metallic  buttons  and 
other  articles.  As  yellow  ocher,  it  is  a  common  material 
for  paint. 

Gdtkite,  Lepidskrokite.  These  are  names  given  to  crystals 'of  U  hy- 
drous pcroxyd  of  iron,  differing  in  composition  from  brown  iron  ore  by 
containing  half  as  much  water.  The  crystals  are  of  a  brown  color,  and 
blood -red  by  transmitted  light  when  subtransparent.  Streak  brownish- 
yellow  to  ocher-yellow.  H==5.  Gr=4-0— 4-2.  Occurs  with  hematite 
et  Eiser/eld  in  Nassau  ;  at  CKften  in  Cornwall ;  in  Siberia  and  else- 
where. Turgite  from  the  Ural,  appears  to  be  identical  with  this  species, 

FRAXKLINITE* 

Monometrlc.    In   octahedral  and  dodecahedral  crystals, 
and  also  coarse  granular  massive.     Color  iron- 
black  ;    streak   dark    reddish-brown.     Brittle. 
H=5*5 — 6-0.     Gr=4-85 — 5-1  ;  acts  slightly 
on  the  magnet. 

Composition :  peroxyd  of  iron  66,  sesquoxyd 
of  manganese  16,  oxyd  of  zinc  17.  Alone  in- 
fusible. At  a  high  temperature  zinc  is  driven  off)  and  is 
deposited  on  the  charcoal ;  with  borax  on  a  platinum  wire, 
in  the  outer  flame,  it  gives  the  violet  color  due  to  manganese  ; 
and  in  -the  inner  flame  on  charcoal,  the  green  color  due  to  iron. 

Dif.  Resembles  magnetic  iron,  but  the  exterior  color  is 
a  more  decided  black.  The  streak  is  not  black,  and  the 
blowpipe  reactions  are  different. 

Obs.  This  is  an  abundant  ore  at  Sterling  and  Hamburgh, 
in  New  Jersey,  near .  the  Franklin  furnace ;  at  the  former 
place,  the  crystals  are  sometimes  4  inches  in  diameter.  It  is 
said  to  occur  also  in  the  mines  of  Altenberg,  near  ALx-la- 
Chapelle. 

Uses.  The  attempts  to  work  this  ore  for  zinc  have  not 
been  successful. 

What  is  said  of  the  uses  of  brown  iron  ore  1  What  is  the  appear- 
ance of  franklinite  ?  What  is  its  composition  ?  How  is  it  distinguish- 
ed from  magnetic  iron  ore  ? 

19* 


METALS* 


ILMETTCTE.  —  Titanic  iron. 

In  crystallization  near  specular  iron.  K  :  R=g5°  59^ 
Often  in  thin  plates  or  seams  in  quartz  ;  also  in  grains. 
Crystals  sometimes  rery  large  and  tabular. 

Color  iron-black  ;  streak  metallic.  Luster  metallic  OT 
submetallic.  H=5  —  6.  Gr=4'5  —  5  ;  acts  slightly  on  thtf 
magnetic  needle. 

Composition  :  oxyd  of  iron,  with  a  variable  proportion  of 
titanic  acid  or  oxyd  of  titanium.  Infusible  alone  before  the 
blowpipe. 

Crichtonite,  ilmenite,  menaccanite,  fiysfatife,  and  iserine^ 
are  names  of  some  of  the  varieties  of  this  species.  The  hys- 
tatite  variety  includes  the  washingtontie  of  Professor  Shepard. 
Octahedral  and  cubic  crystals  of  this  mineral  have  been  found 
with  titaniferous  sand,  which  are  supposed  to  be  pseudo- 
morphotts, 

Dif.  Near  specular  iron,  but  differs  in  the  less  luster  of 
its  crystals,  and  its  metallic  streak. 

Obs.  Crystals  an  inch  or  so  in  diameter  occur  in  War- 
wick, Amity,  and  Monroe,  Orange  county,  N.  Y.  ;  also  near 
Edenville  and  Greenwood  furnace  ;  also  at  South  Royalston 
and  Goshen,  Mass.  ;  at  Washington,  South  Britain,  and 
Litchfied,  Conn.  ;  at  Westerly,  Rhode  Island. 

Uses.     Of  no  value  in  the  arts. 

CHROMIC  IRON.  —  Cliromate  of  Iron. 

Monometric.  In  octahedral  crystals,  without  distinct  clea- 
vage. Usually  massive,  and  breaking  with  a  rough  un- 
polished surface. 

Color  iron-black  and  brownish  -black  ;  streak  dark  brown. 
Luster  submetallic  ;  often  faint.  H  =  5'5.  Gr  =  4'3—  4-5. 
In  small  fragments  attractable  by  the  magnet. 

Composition  :  green  oxyd  of  chromium  60'0,  protoxyd  of 
iron  20*1,  alumina  11*8,  magnesia  7-5.  The  alumina  and 
magnesia  are  variable.  Infusible  alone  before  the  blowpipe. 
Fuses  slowly  with  borax  to  a  beautiful  green  globule. 

Dif.  The  little  luster  of  this  ore  on  a  surface  of  fracture 
is  peculiar  ;  also  its  fine  green  glass  with  borax,  which  dis- 
tinguishes it  from  ores  of  iron  and  other  metals. 

Describe  titanic  iron.  Of  what  does  it  consist  ?  How  does  it  differ 
from  specular  iron  ?  What  is  the  appearance  of  chromic  iron  1  its  com- 
position 1  How  is  it  distinguished  from  other  ores? 


IRON    ORES.  223 

Obs.  Occurs  usually  in  serpentine  rocks,  in  imbedded 
masses  or  veins.  Some  of  the  foreign  localities  are  the 
Gulsen  mountains  in  Styria  ;  the  Shetland  Islands ;  the  de- 
partraent  of  Var  in  France  ;  Silesia,  Bohemia,  etc. 

In  the  United  States,  it  is  abundant  in  Maryland  in  the 
Bare  Hills  near  Baltimore,  and  also  in  Montgomery  county, 
at  Cooptown  in  Harfbrd  county,  and  in  the  north  part  of 
Cecil  county  ;  occurs  also  in  Townsend  and  Westfield,  Ver- 
mont, and  at  Chester  and  Blandford,  Mass.  It  is  also  found 
at  Hoboken,  N.  Y.,  and  at  Milford  and  West  Haven,  Conn. ; 
in  Pennsylvania  in  Little  Britain,  Lancaster  county,  and 
West  Branford,  Chester  county,  and  on  the  Wisahicon,  11 
miles  from  Philadelphia. 

Uses.  The  compounds  of  chrome  are  extensively  used 
as  pigments.  These  compounds  are  obtained  either  from 
chromic  iron  or  the  native  chromate  of  lead,  (see  under 
lead.)  The  chromate  of  lead  and  copper  (vauquelinite)  is 
too  rare  to  be  employed  for  this  purpose.  The  chromate  6f 
potash  is  readily  formed  by  mixing  equal  parts  of  nitre  and 
the  powdered  chromic  iron  and  exposing  the  mixture  in  a 
crucible  to  a  strong  heat  for  some  hours.  The  soluble  part 
is  then  washed  out,  and  the  process  is  repeated  with  the  in- 
soluble portion  (digesting  it  tirst  in  muriatic  acid  to  remove 
the  free  oxyd  of  iron  and  alumina)  till  all  the  ore  is  decom- 
posed. The  colored  liquid  obtained  from  the  washings  is 
carefully  saturated  with  nitric  acid,  and  concentrated  by 
evaporation  till  crystals  of  nitre  cease  to  be  deposited.  Being 
then  set  aside  for  a  week  or  two,  it  gradually  deposits  abun- 
dant crystals  of  the  yellow  chromate  of  potash.  Chromate 
of  lead,  called  also  chrome  yellow,  is  the  most  common  chrome 
paint  used.  It  is  made  by  adding  to  the  liquid  obtained  as 
above  stated,  before  its  crystallization,  a  solution  of  acetate 
of  lead  (sugar  of  lead)  till  it  is  saturated.  The  yellow  pre- 
cipitate washed  out  and  dried,  is  the  chrome  yellow  of  com- 
merce. It  is  used  as  a  yellow  pigment  both  in  oil  and  water 
colors,  calico  printing,  dyeing,  and  porcelain  painting.  This 
material  is  largely  manufactured  at  Baltimore,  Md.  The 
native  nitrate  of  soda  of  Peru,  has  been  suggested  as  a  sub- 
stitute for  nitre  in  the  above  process. 

Another  mode  of  this  manufacture  recently  proposed,  con- 
Where  does  chromic  iron  occur  ?     What  are  its  uses  ?     How  is  the 
ore  treated  ?     What  is  chrome  yellow,  and  how  is  it  made  1 


224 


METALS. 


sists  in  making  a  chromate  of  lime  from  the  chromic  iron* 
It  is  as  follows  :  1.  Pulverize  very  finely  chalk  and  chromic 
iron,  and  mix  the  sifted  material  well  by  means  of  a  revolv- 
ing  barrel.  2.  Calcine  for  nine  or  ten  hours  at  a  bright  red 
heat  in  a  reverberatory  furnace,  when,  if  complete,  the  whole 
has  a  yellowish-green  color,  and  dissolves  entirely  in  muri- 
atic acid.  3.  The  porous  mass  after  being  crushed  under  a 
mill,  to  be  mixed  with  hot  water  and  kept  agitated,  adding 
a  little  sulphuric  acid  till  it  slightly  reddens  blue  litmus 
paper.  4.  Triturated  chalk  should  then  be  added,  and  the 
oxyd  of  iron  is  thus  removed.  5.  After  being  left  quiet  for 
a  while,  the  clear  supernatant  liquid  is  to  be  drawn  off:  it 
contains  bichromate,  with  a  little  sulphate  of  lime.  Tho 
chromate  of  potash  may  then  be  made  from  it  by  adding  car- 
bonate of  potash  ;  the  chromate  of  lead,  by  adding  acetate 
of  lead  ;  chromate  of  zinc,  by  adding  chlorid  of  zinc. 

The  bichromate  of  potash  has  a  fine  red  color,  and  is  much 
used  by  calico  printers.  It  is  made  from  the  chromate  by 
adding  nitric  or  acetic  acid  to  its  solution,  (enough  to  give  it 
a  sour  taste,)  and  setting  it  aside  to  crystallize.  The  green 
oxyd  of  chromium  gives  the  fine  green  color  to  glass  of 
borax  in  blowpipe  experiments  with  chromic  iron  ;  and  it 
is  used  to  produce  this  tint  in  porcelain  and  enamel  painting. 
It  is  the  coloring  ingredient  of  the  emerald,  and  the  emerald, 
colored  chrysoberyl  of  the  Urals ;  and  occurs  in  some  varie- 
ties of  diallage  and  serpentine.  It  has  been  found  native. 
Chromic  acid  is  said  to  be  the  coloring  matter  of  the  red 
sapphire  or  ruby.  With  oxyd  of  tin,  it  affords  a  pink  color, 
which  is  used  in  porcelain  painting. 

COLUMBITE. — Tantalite,  of  European  Chemists. 

Trimetric.  In  rectangular  prisms,  more  or  less  modified. 
Also  massive.  Disseminated  in  the  gangue. 
Cleavage  parallel  to  the  lateral  faces  of  the 
prism,  somewhat  distinct. 

Color  iron-black,  brownish-black ;  often 
with  a  characteristic  iridescence  on  a  surface 
of  fracture  ;  streak  dark  brown,  slightly  red- 
dish. Luster  submetallic,  shining.  Opaque. 

Describe  another  mode  of  treating  chromic  iron  1  What  is  the  color- 
ing ingredient  of  the  emerald  1  what  of  the  red  sapphire  1  What  are 
the  color,  lusfter  and  form  of  columbite  ? 


IRON    ORES.  225 

Brittle.  H=5 — 6.  Gr=5'3 — 6-4.  American  5-3 — 5-71 ; 
Bavarian  5*7 — 6*4. 

Composition  of  an  American  specimen :  columbic  with 
niobic  acid  80'  1,  protoxyd  of  iron  12-6,  protoxyd  of  manga- 
nese 6-0,  oxyd  of  tin  0*1,  oxyds  of  copper  and  lead  0-4.  The 
Bavarian  columbite' contains  also  pelopic  acid,  which  is 
sparingly  found  in  the  American,  and  from  its  high  specific 
gravity  accounts,  as  Prof.  Rose  states,  for  the  difference  in 
lii is  respect  in  the  varieties  from  the  two  countries. 

Infusible  alone  before  the  blowpipe.  With  borax  in  a 
fine  powder  fuses  quite  slowly,  but  perfectly,  to  a  dark  green 
glass,  which  indicates  only  the  presence  of  iron. 

Dif.  Its  dark  color,  submetallic  luster,  and  a  slight  iri- 
descence, together  with  its  breaking  readily  into  angular 
fragments,  will  generally  distinguish  this  species  from  the 
ores  it  resembles. 

Obs.  Occurs  in  granite  at  Bodenmais  in  Bavaria,  and 
also  in  Bohemia.  In  the  United  States,  it  is  found  in  the 
same  rocks,  feldspathic  or  albitic,  at  Middletown  and  Had- 
dam,  Conn. ;  at  Chesterfield  and  Beverly,  Mass.,  and  at 
Acworth,  N.  H.  A  crystal  was  found  at  Middletown,  which 
originally  weighed  14  pounds  avoirdupois  ;  and  a  part  of  it, 
6  inches  in  length  and  breadth,  weighing  61bs.  12oz.,  is  now 
in  the  collections  of  the  Wesleyan  University  of  that  place. 

This  mineral  was  first  made  known  from  American  speci- 
mens, by  Mr.  Hatchett,  an  English  chemist,  and  the  new 
metal  it  was  found  to  contain  was  named  by  him  columbium. 

Ferrotantalite.  This  is  an  allied  mineral,  often  called,  from  its  lo- 
cality at  Kimito  in  Finland,  kimito-lantalile.  It  is  a  neutral  colum- 
bate  of  iron.  H=5 — 6.  Gr=7'2 — 80.  A  variety  from  Broddbo 
contains  8  per  cent,  of  oxyd  of  tin,  with  6  of  tungstic  acid.  Sp.  gr.= 
6-5. 

y0te. — The  metal  columbium  is  also  found  in  pyroehlore,  and  in  the 
yttria  ores,  yttro-columbite,  euxenite,  fergusonite,  and  wOhlerite.  The 
metals  niobium  and  pelopium  are  usually  associated  with  it. 

WOLFRAM. — Tungstate  of  Iron  and  Manganese. 

Trimetric.  In  modified  rhombic  or  rectangular  prisms  ; 
sometimes  pseudomorphous  in  octahedrons  imitative  oftung- 
state  of  lime.  Also  massive.  Color  dark  grayish-black; 

Of  what  does  columbite  consist !  How  does  it  differ  from  other  ores  ? 
Describe  wolfram. 


PETAL'S. 

streak  dark  reddish  brown.     Luster  submetalllc,  shining  cr 
dull.     H=5— 5-5.     Gr=7-l— 7-4. 

Composition  :  tungstic  acid  75-89,  protoxyd  of  ir«m  19'24, 
protoxyd  of  manganese  4-97.  Fuses  with  difficulty.  Gives 
a  green  bead  with  borax,  and  a  deep  red  globule  with  salt  of 
phosphorus. 

Found  often  with  tin  ores.  Occurs  in  Cornwall,  and  at  i 
Zinnwald  and  elsewhere  in  Europe.  In  the  United  States, 
it  is  found  at  Monroe  and  Trumbull,  Conn.  ;  on  Camdage 
farm  near  Blue  Hill,  Me.;  near  Mine  la  Motte,  Missouri^ 
in  the  gold  regions  of  North  Carolina. 

SILICATES    OF    IRC  N. 

There  are  several  compounds  of  silica  andoxyd  of  iron,  none  of  whiclj 
are  of  specia-1  interest  in  an  economical  point  of  view. 

Hedenbergite  is  a  variety  of  augite,  consisting  essentially  of  these  in- 
gredients, (see  page  151.) 

Iron  chrysolite  differs  from  ordinary  chrysolite  in  containing  oxyd  of 
iron  in  place  of  magnesia. 

Isopyre  is  a  black  glassy  amorphous  mineral,  found  in  granite.  H= 
6 — 6-5.  Gr=2-9 — 3.  Consists  of  silica  47"  1,  alumina  13'9,peroxyd  of 
iron  20' 1,  lime  15'4,  oxyd  of  copper  1'9, 

Yenite,  (called  also  lievrite  and  ilvaite.}  Occurs  in  rhombic  prisms, 
often  with  the  sides  much  striated  or  fluted ;  color  black  or  brownish 
black.  Luster  submetallic.  Streak  black,  greenish  or  brownish.  11=. 
55 — 6.  Gr=3'8 — 4'1.  Contains  about  50  to  55  per  cent,  of  oxyd  of 
iron  with  14  of  lime  and  29  of  silca.  Fuses  to  a  black  globule.  From 
the  island  of  Elba  in  large  crystallizations;  also  from  Norway,  Siberia, 
Silesia.  At  Cumberland,  Rhode  Island,  yenite  occurs  in  slender  blade 
or  brownish-black  crystals,  in  .quartz  ^  also  in  Essex  county,  N.  Y. 

The  following  are  hydrous  species,  giving  off  water  when  heated  in 
a  tube  before  the  blowpipe. 

Nontronite  and  pinguite,  are  earthy  almosi  like  clay,  of  a  yellowisi 
or  greenish  color. 

Chloropal  is  a  harder  species,  (H=3 — 4,)  of  a  greenish-yellow  or 
pistachio-green  color-  Grengesite,  thttringile,  knebelite,  and  kirwan- 
•ite,  are  other  allied  species. 

Green  earth.  Includes  different  compounds  of  a  green  earthy  ap- 
pearance. The  green  earth  occupying  cavities  in  amygdaloid  is  near 
chlorite.  It  is  a  silicate  of  the  peroxyd  of  iron  with  some  potash,  mag- 
nesia and  water ;  often  with  other  ingredients.  The  green  grains  of 
<he  green  sand  of  New  Jersey,  consist  of  si  iea  5H>,  alumina  G'4,  pro- 
toxyd of  iron  24'3,  potash  9'9o,  water  7'7. 

Hisingerite,  cronstcdtite,  anihosidtrile , pt  lyhydrite,  sideroschisolite, 
chamoisite,  stilpnomelane,  and  xyhte,  are  names  of  dark  brown  or 
black  species. 

Of  what  does  wolfram  consist?  With  what  ores  is  it  usually  associ- 
ated I  Whal  is  said  of  the  compounds  of  oxyd  of  iron  with  silica] 


IIZOST   ORES.  227 

Crocidotite  hits  a  fibrous  structure  much  resembling  asbestus,  and 
ftfs  been  called  blue  asbestus.  Color  lavender-blue  or  leek-green 
H=4.  Gr=3  2— 33.  From  Southers  Africa, 

Pyrosmalite  occurs  in  hexagonal  prisms  with  a  perfect  basal  cleavage, 
and  pearly  surface.  Color  pale  liver-brown,  grayish,  or  greenish.  H= 
4 — 1-5.  Gr=3'8.  Contains  14  per  cent,  of  eWorld  of  iron,  and  gives 
oil"  fumes  of  muriatic  acid  before  the  blowpipe. 

Iron -zeolite.  A  hydrous  silicate  of  the  oxyds  of  iron  and  manganese, 
tinning  incrustations  at  a  mine  near  Freyberg. 

COPPERAS. — Sulphate  of  Iron,  or  Green  Vitriol. 

Monoclinate.  In  acute  oblique  rhombic  prisms.  M  :  M= 
J82  21  ;  P  :  M=80  37'.  Cleavage  parallel  to  P,  perfect. 
•Generally  pulverulent  or  massive. 

Color  greenish  to  white.     Luster  vitreous.     Subtranspa- 
<rent  to  translucent.    Taste  astringent,  sweetish,  and  metallic. 
Brittle.     H=2.     Gr  =  l-83. 

GomposUi&n:  oxyd  of  iron  25'42,  sulphuric  acid  29-01, 
jwater  45'57.  Becomes  magnetic  before  the  blowpipe. 
•Yields  a  green  glass  with  blowpipe  j  and  a  black  color  with 
a  tincture  of  nut  galls.  On  exposure,  becomes  covered  with 
a  yilowish  powder,  which  is  a  persalt  of  iron. 

O65.     This   species  is  a  result  of  the  decomposition  of 

, pyrites,  which  readily  affords  it  if  moistened  while  exposed  to 

jthe  atmosphere,  as  stated  under  pyrites.     The  old  mine  of 

iRammelsberg  in  the   Hartz,  near  Goslar,  is  its  most  noted 

locality ;  but  it  occurs  wherever  pyrites  is  found. 

Copperas  is  much  used  by  dyers  and  tanners,  on  account  of 
Jits  giving  a  black  color  with  tannic  acid,  an  ingredient  in  nut- 
Jgalls  and  many  kinds  of  bark.  It  for  the  same  reason  forms 
jthe  basis  of  ordinary  ink,  which  is  essentially  an  infusion  of 
;jnutgalls  and  copperas.  It  is  also  employed  in  the  manufacture 
jof  Prussian  blue.  With  prussiate  of  potash,  any  soluble  per- 
jsalt  of  iron,  even  in  minute  quantity,  gives  a  fine  blue  color 
jto  the  solution,  (due  to  the  formation  of  Prussian  blue,)  and 
this  is  a  common  test  of  the  presence  of  iron. 

About  1800  tons  of  copperas  are  used  in  the  United  States 
annually.  The  colcotliar  of  v:triol  is  the  browish-red  oxyd 
!of  iron,  obtained  from  copperas  by  calcination  and  other 
processes.  It  is  much  used  as  a  polishing  powder. 
i  Coquimbite,  or  white  copperas,  and  yellow  copperas,  are  names  of 
Itwo  sulphates  of  the  peroxyd  of  iron.  Pittizite,fibro-ferrite,  are  allied 

"What  is  the  appearance  and  taste  of  copperas  ?  its  composition  ? 
(What  is  its  origin  in  nature  ?  For  what  is  it  used  ? 


228  METALS. 

compounds.     Apalclite  is  still  another,  peculiar  in  containing  bat  4  per 
cent,  of  water. 

Voltnitc  is  a  double  sulphate  of  iron,  alumina,  potash  and  water,  crys- 
tallizing like  alum  in  octahedrons.  From  the  Soifatara,  near  Naples. 

SPATHIC  IRON. — Carbonate  of  Iron* 

Hexagonal.  In  rhombohedrous  and  six-sided  prisms,  easily 
cleavable  parallel  to  a  rhombohedron  of  107 J. 
Faces  often  curved.  Usually  massive,  with  a 
foliated  structure,  somewhat  curving.  Some- 
times in  globular  concretions  or  implanted 
globules. 

Color  light  grayish  to  brown  ;  often  dark  brownish-red,  or 
nearly  black  on  exposure.  Streak  tmcolored.  Luster  pearly 
to  vitreous.  Translucent  to  nearly  opaque.  H— 3 — 4*5. 
Gr=3-7 — 3-85. 

Composition,  when  pure  :  protoxyd  of  iron  61-37,  carbonic 
acid  38'63.  Often  contains  some  oxyd  of  manganese  or 
magnesia,  replacing  part  of  the  oxyd  of  iron.  Before  the 
blowpipe  it  blackens  and  becomes  magnetic  ;  but  alone  it  is 
infusible.  Colors  borax  green.  Dissolves  in  nitric  acid,  but 
scarcely  effervesces  unless  pulverized. 

The  ordinary  crystallized  or  foliated  variety  is  called 
spathic  or  sparry  iron,  because  the  mineral  has  the  aspect  of 
a  spar.  The  globular  concretions  found  in  some  amygda- 
loids  or  lavas,  have  been  called  spherosiderite.  An  argilla- 
ceous variety,  occurring  in  nodular  forms,  is  often  called  clay 
iron  stone,  and  is  abundant  in  the  English  coal  measures. 

Dif.  This  mineral  is  foliated  like  calc  spar  and  dolomite  ; 
but  it  has  a  much  higher  specific  gravity.  It  readily  becomes 
magnetic  before  the  blowpipe. 

Obs.  Spathic  iron  occurs  in  rock  of  various  ages,  and 
often  accompanies  metallic  ores.  The  largest  beds  are  found 
in  gneiss  and  graywacke,  and  also  in  the  coal  formation. 
In  Styria  and  Carinthia,  it  is  very  abundant  in  gneiss,  and 
in  the  Hartz  it  occurs  in  graywacke.  Cornwall,  Alstonmoor 
and  Devonshire,  are  English  localities. 

A  vein  of  considerable  extent  occurs  at  Roxbury,  near 
New  Milford,  Conn.,  in  quartz,  traversing  gneiss  ;  at  Ply- 
mouth, Vt.,  and  Sterling,  Mass.,  it  is  also  abundant.  It  oc- 

Describe  spathic  iron.  What  is  its  constitution  1  What  are  its 
chemical  characters  ?  How  does  it  differ  from  calc  spar?  What  are 
its  varieties  ?  How  does  it  occur? 


1KO\    ORES.  229 

curs  also  at  Monroe,  Conn. ;  in  New  York  state,  in  Antwerp, 
Jefferson  county,  and  in  Hermon,  St.  Lawrence  county.  The 
argillaceous  carbonate  in  nodules  and  beds,  is  very  abun- 
dant in  the  coal  regions  of  Pennsylvania. 

Uses.  This  ore  is  employed  extensively  for  the  manufac- 
ture of  iron  and  steel. 

Thomaite  is  a  carbonate  of  iron  occurring  in  rhombic  prisms.  Gr= 
3-1.  From  the  Siebengebirge  mines.  Junkerite  has  proved  to  be  com- 
mon spathic  iron. 

Mesitine  spar,  (Breunnerite.)  A  carbonate  of  iron  and  manganese, 
occurring  in  yellowish  rhombohedrons  of  107^  14'.  H=4.  Gr=3'3 — 
3-6.  This  includes  much  of  what  is  called  rhomb  spar,  or  brown  spar, 
which  becomes  rusty  on  exposure. 

Oligon  spar.  A  carbonate  of  iron  and  manganese.  Angle  of  rhom- 
bohedron  107°  3'.  Color  yellow  or  reddish-brown.  Gr=3.75. 

VIVIANITE. 

Monoclinate.  In  modified  oblique  prisms,  with  cleavage 
in  one  direction  highly  perfect.  Also  radiated,  reniform, 
and  globular,  or  as  coatings. 

Color  deep  blue  to  green.  Crystals  usually  green  at  right 
angles  with  the  vertical  axis,  and  blue  parallel  to  it.  Streak 
bluish.  Luster  pearly  to  vitreous.  Transparent  to  translu- 
cent;  opaque  on  exposure.  Thin  laminae  flexible.  H  = 
1-5—2.  Gr  =  2-66. 

Composition  :  protoxyd  of  iron  42'4,  phosphoric  acid  28'7, 
water  23-9.  Loses  its  color  before  the  blowpipe  and  be- 
comes opaque  ;  and  if  pulverized,  fuses  to  a  scoria,  which  is 
magnetic.  Affords  water  in  a  glass  tube,  and  dissolves  in 
nitric  acid. 

Dif.  The  deep  blue  color  connected  with  the  softness, 
are  decisive  characteristics.  The  blowpipe  affords  a  con- 
firmatory test. 

Obs.  Found  with  iron,  copper  and  tin  ores,  and  some- 
times in  clay,  or  with  bog  iron  ore.  St.  Agnes  in  Cornwall, 
Bodenmais,  and  the  gold  mines  of  Vorospatak  in  Transylva- 
nia, afford  fine  crystallizations.  In  the  United  States,  good 
crystals  have  been  found  at  Imleytown,  N.  J.  At  Allentown, 
Monmouth  county,  and  Mullica  Hill,  Gloucester  county,  N. 
J.,  are  other  localities.  It  often  fills  the  interior  of  certain 
fossils.  Occurs  also  at  Harlem,  N.  Y.,  in  Somerset  and 


For  what  is  spathic  iron  used  ?     What  is  the  color  and  structure  of 
vivianite  1     Of  what  does  it  consist  ? 
20 


230  METALS. 

Worcester   counties,  Md.,    and  with   bog  ore   in   Stafford 
county,  Va. 

The  blue  iron  earth  is  an  earthy  variety,  containing  about  30  per 
cent,  of  phosphoric  acid.  The  mineral  from  Mullica  Hill  has  been 
called  mullicite. 

Anglarite,  from  Anglar,  France,  is  a  similar  mineral,  with  less  phos- 
phoric acid. 

Triphylinc  occurs  in  cleavable  masses,  of  a  greenish-gray  or  bluish 
color.  H=5.  Gr=3  6.  It  is  an  anhydrous  phosphate  of  the  pro- 
toxyds  of  iron,  and  manganese,  with  some  lithia.  From  Bodenmais  in 
Bayern. 

Green  iron  stone,  (kraurite,)  alluaudite,melanchlor,nnd  beraunite,are 
names  of  phosphates  of  the  peroxyd  of  iron.  Color  of  the  first  two,  dull 
leek-green  ;  structure  fibrous.  Luster  silky.  Color  of  the  third,  black  ; 
of  the  fourth,  hyacinth-red,  becoming  darker  on  exposure. 

Cacoxene.  This  is  a  handsome  species,  occurring  in  radiated  silky 
tufts  of  a  yellow  or  yellowish-brown  color.  H=3 — 4.  Gr=3'38.  It  is  a 
phoephate  of  alumina  and  iron.  It  differs  from  Wavellite,  which  it  re- 
sembles in  its  more  yellow  color  and  iron  reactions.  It  also  resembles 
carpholite,  but  has  a  deeper  color.  It  occurs  on  brown  iron  ore  in 
Bohemia.  Also  with  specular  iron  at  the  Sterling  iron  mines  at 
Antwerp,  Jefferson  county,  New  York,  and  at  Mount  Defiance,  near 
Ticonderoga. 

Carphosiderite  is  another  yellow  phosphate  of  iron  from  Greenland. 
It  occurs  in  reniform  masses. 

ARSENATES    OF    IRON. 

Cube  ore.  Occurs  in  cubes  of  dark  green  to  brown  and  red  colors. 
Luster  adamantine,  not  very  distinct.  Streak  greenish  or  brownish. 
H=2'5.  Gr=3.  It  is  a  hydrous  arsenate  of  the  peroxyd  of  iron,  con- 
taining 38  per  cent,  of  arsenic  acid.  From  the  Cornwall  mines  ;  also 
from  France  and  Saxony. 

Scorodite.  Crystallizes  in  rhombic  prisms,  modified.  M  :  M=119° 
2'.  Color  pale  leek-green  or  liver  brown.  Streak  uncolored.  Luster 
vitreous  to  subadamantine.  Subtransparent  to  nearly  opaque.  H= 
3-5 — 4.  Gr=3'l — 3-3.  Scorodite  is  a  hydrous  arsenate  of  the  per- 
oxyds  of  iron,  containing  50  per  cent,  of  arsenic  acid.  From  Saxony, 
Carinthia,  Cornwall,  and  Brazil. 

It  occurs  in  minute  crystals  near  Edenville,  N.  Y.,  with  arsenical 
pyrites.  The  name  of  this  species  is  from  the  Greek  skorodon,  garlic, 
alluding  to  the  odor  before  the  blowpipe. 

Iron  sinter  is  a  yellowish  or  brownish  hydrous  arsenate  of  the  peroxyd 
of  iron,  containing  but  30  per  cent,  of  arsenic  acid.  Arseno-siderite  Is 
another  fibrous  arsenate,  containing  34  per  cent,  of  arsenic  acid. 

Symplesite  is  a  blue  or  green  mineral,  supposed  to  be  an  arsenate  of 
the  protoxyd  of  iron.  Its  crystals  are  right  rhomboidal,  with  a  perfect 
cleavage.  H=2'5.  Gr=2.96.  From  Voigtland. 

Oxalate  of  iron.  This  is  a  soft,  yellow,  earthy  mineral  of  rare  oc- 
currence. It  blackens  instantly  in  the  flame  of  a  candle.  Occurs  in 
Bohemia  ;  it  is  supposed  to  have  resulted  from  the  decomposition  of 
succulent  plants. 


METALS.  231 


GENERAL  REMARKS  ON  IRON  AND  ITS  ORES. 

The  metal  iron  has  been  known  from  the  most  remote  historical 
period,  but  was  little  used  until  the  last  centuries  before  the  Christian 
era.  Bronze,  an  alloy  of  copper  and  tin,  was  the  almost  universal  sub- 
stitute, for  cutting  instruments  as  well  as  weapons  of  war,  among  the 
ancient  Egyptians  and  earlier  Greeks ;  and  even  among  the  Romans 
(as  proved  by  the  relics  from  Pompeii)  and  also  throughout  Europe,  it 
continued  long  to  be  extensively  employed  for  these  purposes. 

The  Chalybes,  bordering  on  the  Black  Sea,  were  workers  in  iron  and 
steel  at  an  early  period  ;  and  near  the  year  500  B.  C.,  this  metal  was 
introduced  from  that  region  into  Greece,  so  as  to  become  common  for 
weapons  of  war.  From  this  source  we  have  the  expression  chalybeate 
applied  to  certain  substances  or  waters  containing  iron. 

The  iron  mines  of  Spain  have  also  been  known  from  a  remote  epoch, 
and  it  is  supposed  that  they  have  been  worked  "  at  least  ever  since  the 
times  of  the  later  Jewish  kings ;  first  by  the  Tynans,  next  by  the  Car- 
thagenians,  then  by  the  Romans,  and  lastly  by  the  natives  of  the  coun- 
try." These  mines  are  mostly  contained  in  the  present  provinces  of 
New  Castile  and  Aragon.  Elba  was  another  region  of  ancient  works, 
"  inexhaustible  in  its  iron,"  as  Pliny  states,  who  enters  somewhat  fully 
into  the  modes  of  manufacture.  The  mines  are  said  to  have  yielded 
iron  since  the  time  of  Alexander  of  Macedon.  The  ore  beds  of  Styria 
in  Lower  Austria,  were  also  a  source  of  iron  to  the  Romans. 

Iron  ores.  The  ores  from  which  the  iron  of  commerce  is  obtained, 
are  the  spathic  iron  or  carbonate,  magnetic  iron,  specular  iron,  brown 
iron  ore  or  hematite,  and  bog  iron  ore.  In  England,  the  principal  ore 
used  is  an  argillaceous  carbonate  of  iron,  called  often  clay  iron  stone, 
found  in  nodules  and  layers  in  the  coal  measures.  It  consists  of  car- 
bonate of  iron,  with  some  clay,  and  externally  has  an  earthy,  stony 
look,  with  little  indication  of  the  iron  it  contains  except  in  its  weight. 
It  yields  from  20  to  35  per  cent,  of  cast  iron.  The  coal  basin  of 
South  Wales,  and  the  counties  of  Stafford,  Salop,  York,  and  Derby, 
yield  by  far  the  greater  part  of  the  English  iron.  Brown  hematite 
is  also  extensively  worked.  In  Sweden  and  Norway,  at  the  famous 
works  of  Dannemora  and  Arendal,  the  ore  is  the  magnetic  iron  ore, 
— -1  is  nearly  free  from  impurities  as  it  is  quarried  out.  It  yields  50  to 

per  cent,  of  iron.  The  same  ore  is  worked  in  Russia,  where  it 
nds  in  the  Urals.  The  Elba  ore  is  the  specular  iron.  In  Germany, 
ria,  and  Carinthia,  extensive  beds  of  the  spathic  iron  are  worked. 

e  bog  ore  is  largely  reduced  in  Prussia. 

In  the  United  States,  all  these  different  ores  are  worked.  The  local- 
ties  are  already  mentioned.  The  magnetic  ore  is  reduced  in  New 
~ngland,  New  York,  northern  New  Jersey,  and  sparingly  in  Pennsyl- 


What  was  the  usual  substitute  for  iron  among  the  ancients?  What 
said  of  the  Chalybes  ?  What  of  the  working  of  the  Spanish  mines] 

f  hat  of  the  Elba  mines  1  What  are  the  common  ores  of  iron  ?  What 
said  of  the  most  common  in  England  ?  in  Sweden  and  Norway?  at 

Iba,  Styria,  and  Carinthia  ?     What  ores  abound  in  the  United  States  ? 


232  METALS. 

vania  and  other  states.  The  brown  hematite  is  largely  worked  along 
Western  New  England  and  Eastern  New  York,  in  Pennsylvania,  and 
many  states  south  and  west.  The  earthy  argillaceous  carbonate  like 
that  of  England,  and  the  hydrate,  are  found  with  the  coal  deposits,  and 
are  a  source  of  much  iron. 

The  several  kinds  of  ore  differ  somewhat  in  the  quality  of  the  iron 
they  afford  ;  but  the  greatest  part  of  the  supposed  difference,  if  we  ex- 
cept the  bog  ore,  depends  on  the  mode  of  working,  and  the  use  of  pro- 
per fluxes  in  the  right  proportion.  The  bog  ore  (a  bog  formation)  often 
contains  phosphorus  from  animal  decomposition,  and  generally  yielda 
a  brittle  product,  though  from  its  fusibility  good  for  some  kinds  of 
casting. 

Mode  of  Assay.  In  the  assay  of  ores  in  the  dry  way,  for  economical 
purposes,  somewhat  different  means  are  used  for  the  different  ores.  As 
in  the  reduction  in  the  large  way,  the  object  is  to  separate  the  iron  from 
the  oxygen  with  which  it  is  united,  and  from  the  impurities  clay,  lime, 
or  quartz,  if  such  be  present. 

With  the  pure  oxyds,  or  the  carbonate  in  a  pure  state,  a  simple  mix- 
ture of  the  pulverized  ore  and  charcoal  strongly  heated  in  a  crucible, 
will  effect  a  reduction.  But  it  is  found  better  to  add  carbonate  of  lime 
or  burnt  lime,  with  clay,  or  glass,  or  borax,  which  fuse  into  a  slag,  and 
besides  aiding  the  reduction,  protect  the  reduced  iron  from  combustion. 
For  specular  iron,  with  10  parts  of  the  ore  finely  pulverized,  mix  as 
much  chalk  or  limestone,  6  to  8  parts  of  bottle  glass,  and  sixteenth  or 
a  twentieth  of  the  whole  by  weight  of  charcoal.  For  a  magnetic  iron 
ore,  mix  with  10  parts  of  the  ore  12  of  glass,  and  as  much  chalk,  with 
one  part  of  charcoal ;  or,  say  3  parts  of  each  burnt  lime  and  burnt  clay, 
and  2^  of  charcoal.  For  a  brown  hematite,  10  parts  of  burnt  lime,  as 
many  of  burnt  clay,  and  3  of  charcoal.  These  proportions,  taken  from. 
Mushet,  are  not  given  as  invariably  necessary,  but  simply  to  guide  the 
experimenter.  The  fitness  of  the  proportions  is  to  be  determined  from 
the  result.  If  the  slag  is  clear  and  nearly  colorless,  the  reduction  is 
perfect.  If  dark  colored,  it  contains  unreduced  oxyd,  and  too  much 
glass  or  clay  may  have,  been  added  ;  if  opaque  or  porcellanous,  too 
much  lime  has  been  used.  In  the  case  of  an  argillaceous  ore,  the  pro- 
portions of  lime  and  glass  should  be  determined  from  the  proportions  of 
lime  and  clay  in  the  ore. 

.  The  prepared  ore  with  the  fluxes,  well  mixed,  is  placed  in  a  crucible 
lined  with  moistened  and  well  compacted  charcoal  dust ;  the  crucible  is 
filled  with  charcoal,  and  closed  with  a  luted  lid  of  fire  clay.  The 
heat  should  be  very  slowly  raised,  not  using  the  bellows  for  three  quar- 
ters of  an  hour,  and  finally  sustained  for  a  quarter  of  an  hour  at  a  white 
heat,  and  then  the  crucible  may  be  removed  and  the  button  of  cast  iron, 
after  cooling,  taken  out. 

Redaction  of  ores.  In  the  reduction  of  iron  ores,  the  simplest  and 
oldest  process  consists  in  heating  the  pounded  ore  with  charcoal  in  an 
open  forge,  (see  beyond,  page  2.'J7.)  By  the  improved  process,  the  ore 
is  heated  in  a  blast  furnace  along  with  charcoal,  coke,  or  mineral  coal. 

What  is  said  of  the  iron  from  different  ores  ?  De  cribe  the  general 
mode  of  assaying  iron  ores  ]  What  is  the  usual  mode  of  reduction  ? 
Describe  the  blast  furnace. 


IRON    ORES. 


23 


and  also  a  certain  proportion  of  some  flux,  usually  limestone.  The 
lime  forms  a  glass  with  the  silicious  impurities  of  the  ore,  while  the 
carbon  (first  becoming  carbonic  oxyd)  takes  the  oxygen  which  is  in 
combination  with  the  metal.  A  small  proportion  of  the  carbon  also  en- 
ters into  the  metal  after  it  is  reduced,  giving  it  the  fusibility  it  has  as 
cast  iron. 

Before  describing  the  process,  a  brief  description  may  be  given  of  a 
blastfurnace.*  The  folio  wing,  figure  (excluding  the  structure  on  the 
right,  to  be  afterwards  explained,)  represents  the  essential  features  of  a 
furnace,  in  an  exterior  side  view. 

1 


It  is  essentially  a  broad  truncated   four-sided  pyramid  of  brick  and 
stone,  containing  within  a  cavity  where  the  ore  is  heated  and  reduced. 

*  I  am  indebted  to  Mr.  S.  S.  Haldeman  for  the  following  figures  and 
their  descriptions.     They  are  l-20th  of  an  inch  to  a  foot.     The  furnace 
was  built  for  anthracite,  as  is  explained  beyond.     It  is  a  model  of  the 
fine  works  near  Columbia,  Pa.,  owned  by  the  Messrs.  Haldeman. 
20* 


234 


METALS. 


The  annexed  figure  2,  exhibits  the  interior  laid  open.     The  main 
structure  is  called  the  stack.     Of  the  interior  cavity,  the  lower  part, 
2  H,    h,  is    the   hearth,  H  is   four- 

sided  ;  B  B,  the  boshes,*  having 
nearly  the  shape  of  a  funnel,  ex- 
cept that  it  is  square  below  ;  above 
b,  is  the  proper  furnace,  usually 
about  30  feet  high  ;  below  the  cru- 
cible, lies  the  hearth,  commonly  of 
refractory  grit  rock.  The  furnace 
is  circular,  and  is  lined  with  fire 
brick  (/)  ;  next  to  this,  is  a  layer  of 
dry  sand  (r,)  and  then  one  of  brick 
(r1,}  constituting  the  inner  part  of 
the  irtack.  The  layer  of  sand  al- 
lows the  interior  to  expand  by 
heat,  without  cracking  the  exte- 
rior ;  and  moreover,  the  whole,  /, 
r,  r',  may  be  removed  for  repairs 
without  injuring  the  exterior  work. 
At  t,  is  one  of  the  twiers,  (or  tuyeres,)  the  tubes  by  which  the  blast  of 
air  is  driven  into  the  furnace.  At  m,  is  a  partial  partition  of  fire  brick, 
called  the  tymp,  separating  the  back  and  front  of  the  hearth,  but  not 
extending  to  the  bottom  or  hearth-stone.  The  hearth-stone  is  made  of 
a  refractory  grit  rock. 

In  each  side  of  the  four-sided  stack,  at  bottom,  there  is  a  door-like  or 
arched  opening,  (A,  figs.  J ,  2,)  which  extends  in  to  the  stonework  that  en- 
closes the  hearth,  'i  hree  of  these  opening  are  called  the  twier-arches, 
and  the  other  is  the  front  or  working  arch  ;  the  twiers  enter  by  the 
twier-arches  to  the  interior,  and  at  t,  (fig.  1,)  is  shown  the  place  of  en- 
trance of  one.  The  view  in  figure  1,  gives  a  front  view  of  a  twier  arch  ; 
and  in  figure  2,  at  A,  there  is  a  tide  view,  with  the  twier  in  place. 
3  To  p:  event  the  melted  metal, 

which  often  rises  above  the 
twiers,  from  flowing  into  the 
blast  pipe,  in  case  of  the  b*last 
being  accidentally  checked, 
there  is  at  V  (fig.  2)  a  valve, 
which  is  raised  by  the  blast  and 
closes  when  it  stops  ;  and  at  k, 
a  place  for  inserting  a  rod  to 
remove  any  slag  that  may  cling 
to  the  twier. 

Figure  3, is  a  horizontal  sec- 
tion, at  bottom  ;  A,  A,  A,  are 
the  twier  arches,  separated  by 
the  masonry  of  the  stack  ;  H, 
h,  the  position  of  the  hearth  or 
crucible  ;  m  is  the  tymp  be- 
tween H  and  h;  t,  t,  t,  are  the 


*  This  word  is  from  the  German  word  boschung,  a  slope.    H. 


IRON    ORES. 

twiers,  the  three  blast  tubes  of  which  connect  with  a  common  tube  that 
extends  round,  by  the  passage  g  g,  (figs.  1,  3,)  in  the  form  of  a  semi- 
circle, and  receives  the  blast  through  the  tube  p.  The  dotted  circle 
within  corresponds  to  the  inner  outline  of  the  tire  brick  lining  of  the 
widest  part  of  the  furnace. 

The  melted  iron  runs  into  the  lower  part  of  the  hearth,  and  is  covered 
by  the  cinder.  It  is  prevented  from  running  out  by  the  damstone  c, 
(figs.  '2,  3)  ;  and  farther  to  hinder  the  metal  from  being  forced  out  by 
the  blast,  clay  is  rammed  beneath  the  tymp  around  the  twiers  and  upon 
the  surface  at  h,  where  it  is  retained  by  heavy  iron  plates.  These 
plates  are  raised  every  few  hours  to  allow  the  cinder  to  run  off",  which 
passes  out  over  the  damstone,  along  the  dust-plate,  c  i,  (figs.  2, 3.)  The 
metal  is  drawn  off  every  twelve  hours  at  the  lower  level  a,  through  an 
aperture  at  the  bottom  of  the  dams-tone. 

Great  economy  in  making  iron  has  of  late  been  secured  by  heating 
the  blast  to  three  to  six  hundred  Fahrenheit.  The  cooling  effect  of  the 
vast  volumes  of  air  thrown  into  the  furnace  is  avoided  ;*  and  this  is  ab- 
solutely necessary  when  anthracite  coal  is  used,  as  is  the  case  in  many 
works  of  recent  construction.  In  the  view  above  given,  f,  f,  (fig.  2,) 
represent  two  (out  of  three)  passages  in  the  upper  part  of  the  furnace, 
by  which  the  waste  flame  is  led  off",  first  to  heat  boilers  at  W,  W,  (fig. 
1,)  and  then  to  a  hot-oven  chamber,  o.  In  the  last  there  is  a  great 
number  of  iron  pipes,  arranged  in  series  ;  the  blast  by  the  action  of  the 
engine,  is  thrown  through  all  the  pipes  in  succession,  and  after  being 
thus  heated, flows  on  to  p,  (fig.  3,)  whence  it  passses  to  the  twiers,  (t,  f, 
f.)  When  the  engine  is  separated  from  the  furnace,  the  oven  is  usually 
placed  upon  the  front  side  (instead  of  back)  of  the  top,  and  the  flame 
passes  in  by  a  single  aperture.  The  works  here  figured  are  situated 
upon  a  side  hill.  It  is  important  that  the  blast  should  not  be  too  great, 
as  it  wastes  the  metal  by  oxydation  ;  and  at  the  same  time  it  should  be 
•ufficiently  copious  to  supply  the  requisite  qantity  of  oxygen. 

The  first  step  in  the  process  of  reduction,  consists  in  roasting  the  ore 
to  drive  oflfany  volatile  ingredients,  and  open  its  texture.  This  is  effect- 
ed by  piling  the  ore  in  heaps,  made  of  alternate  layers  of  coal  or  coke 
and  ore,  covering  up  the  heap  loosely  with  earth  and  firing  it.  The 
carbonic  acid,  if  it  contains  any,  the  moisture,  and  any  sulphur  present, 
are  thus  expelled,  and  the  ore  is  in  a  looser  state  for  reduction.  The 
furnace  is  filled  with  coal  and  slowly  heated  up — ten  or  twelve  days 
being  required  for  this,  to  avoid  the  effect  of  too  sudden  heat  on  the  fur- 
nace. The  charge,  next  to  be  added,  consists  of  coal,  the  roasted  ore, 
and  limestone,  (if  this  be  the  flux,)  in  certain  proportions,  and  it  is  car- 


What  is  said  of  the  hot  blast  ?  Describe  the  method  of  heating  the 
engine,  and  air  of  the  blast.  Mention  the  several  steps  in  the  process 
of  reduction. 

*  The  weight  of  air  thrown  into  a  Glasgow  furnace  in  24  hours,  has 
been  estimated  at  6192  cwt.,  or  6292  cubic  feet  per  minute,  while  the 
whole  weight  of  coke,  ore  and  limestone  added  in  the  same  time,  was 
only  666^  cwt.  In  ordinary  cases,  the  weight  of  the  air  is  at  least  four 
times  as  much  as  that  of  the  charges. 


236  METALS. 

ried  to  the  top  of  the  furnace,  often  by  a  railway,  and  thrown  in  at  inter- 
vals  of  an  half  hour  or  so,  as  the  coal  sinks,  so  that  the  furnace  is  kept 
full.  The  charge  at  the  top  of  the  furnace  is  two  days  or  more  in  de- 
scending to  where  it  comes  within  the  direct  action  of  the  blast.  The 
fusion  of  the  ore  finally  takes  place  a  short  distance  above  the  twiers,  and 
its  reduction  is  completed  at  the  same  time  by  the  burning  coal  and  flux  ; 
in  a  few  hours  the  hearth  fills  with  metal  and  slag,  and  as  it  accumulates, 
the  fused  iron  displaces  the  slag  which  is  continually  running  over  and 
conveyed  off  by  the  workmen  :  the  metal  being  let  out  below  by  remov- 
ing a  luting  of  clay,  is  run  into  moulds  of  sand,  to  form  pigs — oblong 
masses  of  about  180  pounds  each.  The  slag  in  this  process  serves  to 
protect  the  metal  from  combustion  as  it  is  reduced.  Its  color  and  condi- 
tion indicate  the  success  of  the  reduction.  If  of  a  dark  color  and  heavy, 
it  shows  that  all  the  ore  is  not  reduced,  and  much  metal  lost;  probably 
owing  to  too  little  coal  or  too  rapid  working.  If  dark  vitreous,  with 
streaks  of  green,  there  is  some  oxyd  of  iron  carried  off  by  the  silica, 
which  may  probably  be  remedied  by  adding  more  lime  to  take  up  the 
silica.  If  light  colored,  all  is  going  on  well.* 

The  proportion  of  fluxes  depends  on  the  ore  and  its  condition,  and 
no  general  rule  can  be  given.  With  the  argillaceous  carbonate  of  iron 
of  Staffordshire,  limestone  alone  is  used,  10  to  12  per  cent,  being  em- 
ployed for  45  per  cent,  of  ore,  and  45  of  coke.  Even  this  addition  is 
unnecessary  when  the  ore  is  associated  with  much  lime.  For  the  ordi- 
nary argillaceous  ores,  the  weight  of  limestone  used  is  about  one-fourth 
the  weight  of  the  ore,  or  from  one-third  to  one-sixth.  When  there  is 
no  silica  in  the  ore,  it  is  added  in  nearly  equal  proportions  with  the 
lime  and  other  earthy  ingredients  present.  Previous  assays  must  de- 
termine what  is  required  for  each  variety  of  ore.  The  brown  hematite 
is  easily  reduced,  and  requires  much  coal  with  a  slow  process,  or  only 
a  white  iron  is  produced  ;  8  to  12  per  cent,  of  limestone  is  added  to  a 
charge  as  a  flux. 

Good  metal  is  strong  of  a  dark  gray  color,  with  a  granular  texture, 
and  runs  fluid  when  melted  ;  while  the  bad  metal  is  light  colored  and 
brittle,  and  runs  thick  and  sluggish.  There  are  numbers  1*,  2,  3,  4,  in 
market,  including  the  two  kinds  just  described  and  two  intermediate 
grades.  Number  1  is  best  fitted  for  castings,  as  it  contains  the  most 
carbon  and  is  more  fusible  than  the  others.  Cast  iron  sometimes  con- 
tains a  trace  of  silicium  without  injury,  and  according  to  Berzelius,  the 
best  Swedish  iron  contains  after  it  is  made  into  wrought  iron  1-20  per 
cent,  of  silicium.  Sulphur  and  phosphorus  are  highly  deleterious,  ex- 
cept when  a  fusible  metal  is  desired  with  the  strength  comparatively 
unessential. 

Wrought  or  malleable  iron.  As  cast  iron  owes  its  fusibility  princi- 
pally to  the  carbon  present,  the  change  of  cast  to  wrought  iron,  called 

What  is  said  of  the  slag  ?  On  what  does  the  proportion  of  fluxes 
depend  1 

*  The  slag  from  Merthyr  Tydvil,  in  South  Wales,  afforded  Berthier  on 
analysis,  silica  40-4,  lime  38'4,  magnesia  5'2,  alumina  11 -2,  protoxyd 
of  iron  3'8,  and  a  trace  of  sulphur. 


IRON    ORES  2S7 

refining,  must  consist  in  the  removal  of  this  carbon  ana  any  remaining 
impurities.  This  is  done  by  burning  it  out,  and  for  this  purpose  the 
poorer  kinds  of  cast  iron  answer  as  well  as  the  best.  Formerly  the 
metal  was  mehed  three  or  four  times,  and  then  hammered  with  a  large 
forging  hammer  to  remove  the  scoria.  In  the  next  improvement,  the 
metal  while  in  fusion  was  stirred  for  a  while  to  effect  the  more  com- 
plete combustion  of  the  carbon  ;  and  in  this  way  it  gradually  lost  its  fusi- 
bility and  became  stiff  enough  for  forging.  This  process  is  called  pud- 
dling. The  metal  passes  first  through  one  fusion  as  preparatory.  It  ia 
next  placed  on  plates  in  a  furnace  of  the  reverberatory  kind,  the  metal 
being  loosely  piled  in  the  middle  of  the  horizontal  furnace  ;  3£  cwt.  is 
an  ordinary  charge.  The  flame  plays  over  it,  and  in  half  an  hour  it 
begins  to  melt.  The  workmen  now  stir  it  about,  occasionally  dashing 
in  a  scoopful  of  water.  The  metal  gives  off  freely  bubbles  of  gas,  which 
burn  with  a  blue  flame,  (carbonic  oxyd) ;  in  about  twenty  minutes  the 
whole  falls  to  pieces  like  a  coarse  gravel,  and  a  lurid  flame  appears  over 
it.  The  whole  is  still  kept  in  motion  and  well  heated,  and  soon  it  be- 
gins to  unite  again,  when  it  is  separated  into  several  lumps  of  the  size 
of  three  or  four  bricks.  These  masses  as  they  assume  a  clotty  consis- 
tency (sometimes  called  "  coming  into  nature,")  are  drawn  from  the 
furnace  and  dolleyed  or  stamped  into  cakes  with  hammers.  The  plates 
are  thrown  while  hot  into  water,  which  renders  them  brittle  ;  they  are 
then  broken  into  pieces,  again  placed  togeiher  in  the  furnace,  heated  to 
a  welding  heat,  and  finally  forged  under  a  ponderous  hammer,  moved  by 
machinery,  into  short  thick  bars  called  blooms.  100  parts  of  cast  iron 
yield  about  63  of  blooms.  Some  of  the  steps  in  this  process  are  often 
neglected  in  making  the  ordinary  iron. 

It  has  been  found  that  full  24  per  cent,  of  the  gas  escaping  from  an 
iron  furnace  is  carbonic  oxyd,  and  in  the  boshes  this  is  the  only  gas. 
This  gas  has  been  used  as  fuel  in  the  refining  of  the  iron,  and  by  this 
means  the  whole  expense  of  fuel  for  refining  is  saved.  (See  the  Amer. 
Jour.  Sci.,  vols.  i.  and  ii.,2d  ser.,  where  the  theory  of  the  blast  furnace 
is  well  explained.) 

The  iron  produced  is  said  to  be  cold  short  if  it  is  brittle  when  cold, 
and  this  has  been  attributed  to  the  presence  of  silicium.  It  is  termed 
red  short  when  it  becomes  brittle  on  heating. 

Cast  iron  is  also  changed  to  malleable  iron  by  covering  castings  with 
powdered  hematite  or  other  oxyd  of  iron,  and  exposing  to  heat  below 
fusion.  The  carbon  is  removed  by  the  oxygen  of  the  oxyd.  The  scales 
of  oxyd  thrown  off  in  the  forging  of  iron  are  much  used.  This  process 
was  first  introduced  in  1804,  and  is  one  of  great  importance  in  the  arts. 

Malleable  iron  is  also  obtained  directly  from  the  ore  by  a  single  fusion 
in  what  is  called  a  Catalan  forge.  It  has  a  rectangular  crucible  or  basin 
below  the  fire,  about  18  inches  by  21  in  width  and  J  7  inches  deep.  The 
twier  enters  about  9£  inches  above  the  bottom  and  receives  the  blast 
from  a  water-blowing  machine  ;  and  it  admits  of  a  change  of  position 
so  as  to  give  a  change  of  direction  to  the  blast  as  is  required  in  the 

Describe  the  manufacture  of  wrought  from  cast  iron.  How  is  the 
gas  used  in  heating  ?  What  are  cold  short  and  red  short  iron  ?  What 
other  mode  is  there  of  rendering  cast  iron  malleable  ?  Describe  a  mode 
of  obtaining  malleable  iron  direct  from  the  ore. 


238  METALS. 

different  stages  of  the  process.  The  ore  after  a  previous  roasting  in  a 
kiln,  is  pounded  up  and  sifted  ;  the  coarser  part  is  piled  up  in  the  forge 
on  the  side  opposite  the  blast,  and  charcoal  fills  up  the  rest  of  the  space. 
After  the  heat  is  well  up,  the  finer  siftings  are  thrown  at  intervals  upon 
the  charcoal  fire.  The  basin  below,  which  has  been  previously  lined 
with  two  or  three  coats  of  poundf d  charcoal,  or  loam  and  charcoal,  re- 
ceives the  iron  as  it  is  reduced  and  runs  down.  The  slag  is  occasionally 
removed  from  the  surface  of  the  basin  through  holes  opened  for  "ft*£ 
purpose.  The  iron,  when  sufficiently  accumulated,  is  taken  out  in  a 
pasty  state  and  at  once  forged.  The  process  usually  lasts  five  or  six 
hours.  A  lump  or  bloom  of  malleable  iron  is  thus  produced  in  three  or 
four  hours.  This  cheap  and  simple  process  has  long  been  used  in  Cat- 
alonia, and  it  is  hence  called  the  method  of  the  Catalan  forge.  By  a 
slow  operation,  and  but  a  small  quantity  of  siftings,  worked  with  an 
upraised  twier,  the  proportion  of  steel  obtained  by  the  process  is  in- 
creased. This  mode  of  reduction  is  adapted  only  for  the  purer  and 
more  fusible  ores  ;  and  moreover  it  requires  a  large  consumption  of  fuel 
and  is  attended  by  a  considerable  loss.  The  argillaceous  ore  of  the  coal 
region  would  yield  only  an  iron  glass  in  a  Catalan  forge. 

By  another  mode  of  reduction,  the  iron  ore  coarsely  powdered  is 
mixed  with  coal  in  certain  proportions,  or  a  material  containing  the 
requisite  amount  of  carbon,  and  the  charge  is  heated  in  a  reverberatory 
furnace  till  reduction  has  taken  place.  The  carbon  carries  off  the 
oxygen  of  the  ore,  and  if  the  proper  proportions  have  been  employed,  it 
leaves  a  mass  of  malleable  iron  behind. 

Steel.  Wrought  iron  is  changed  to  steel  by  a  process  called  cemen- 
tation. The  best  iron  is  heated  with  charcoal ;  a  portion  of  carbon  is 
thus  absorbed,  and  the  iron  at  the  same  time  acquires  a  blistered  sur- 
face, and  becomes  fine  grained  and  fusible.  When  the  blistered  steel 
is  drawn  down  into  smaller  bars  and  beaten,  it  forms  tilted  steel;  and 
this  broken  up,  heated,  welded,  and  agrun  drawn  out  into  bars,  forms 
shear  steel.  Cast  steel  is  prepared  by  fusing  blistered  steel  with  a  flux 
and  casting  it  into  ingots,  and  then  by  gentle  heating  and  careful  ham- 
mering or  rolling,  giving  it  the  form  of  bars. 

Steel  is  al^o  formed  direct  from  certain  ores  of  iron,  more  particularly 
when  oxyd  of  manganese  is  associated  with  them,  and  especially  from 
the  spathic  iron,  which  often  contains  a  portion  of  carbonate  of  manga- 
nese. The  oxygen  of  the  manganese  is  said  to  remove  part  of  the  car- 
bon from  the  cast  iron,  and  thus  reduce  it  to  the  state  of  steel.  There 
are  1  or  2  per  cent,  of  manganese  in  the  metal  thus  obtained.  The 
product  is  of  inferior  quality  as  steel,  but  is  largely  manufactured  in 
Germany.  The  wootz  of  India  is  a  steel  obtained  from  a  black  ore  of 
iron,  in  a  furnace  even  simpler  than  the  Catalan  forge.  It  is  said  to 
contain  a  minute  proportion  of  silicium  and  aluminium. 

The  amount  of  iron  manufactured  in  the  United  States  in  1847,  (half 
of  it  in  Pennsylvania,)  was  700,000  tons;  in  Great  Britain,  in  1846, 
2,200,000  tons;  in  France,  in  1845,  450,000;  in  Russia,  in  1845, 
400,000  ;  in  Sweden,  in  1846,  145,000  ;  other  parts  of  Europe,  (Aus- 
tria, Belgium,  Germany,)  700,000  tons. 

How  is  steel  made  1  Describe  the  kinds  of  steel.  How  i,s  sfeel  wade 
direct  from  ores  of  iron  ? 


METALS.  239 


5.     MANGANESE. 

The  ores  of  manganese  have  a  specific  gravity  below  5*2. 
They  afford  a  violet-blue  color  with  borax  or  salt  of  phos- 
phorus, in  the  outer  flame  of  the  blowpipe  ;  and  on  heating 
the  oxyd  with  muriatic  acid,  fumes  of  chlorine  are  given  out 
which  are  derived  from  the  acid. 

MANGANESE    SPAR. 

Monoclinate.  In  oblique  rhomboidal  prisms,  with  one 
distinct  cleavage  ;  usually  large  massive,  with  the  cleavage 
often  indistinct 

Color  reddish,  usually  deep  flesh-red ;  also  brownish, 
greenish,  or  yellowish,  when  impure  ;  streak  uncolored. 
Luster  vitreous.  Transparent  to  opaque.  Becomes  black 
on  exposure.  H  =  5'5 — 6-5.  Gr=3-4 — 3-7. 

Composition  :  oxyd  of  manganese  52 '6,  silica  39*6,  oxyd 
of  iron  4*6,  lime  and  magnesia  1*5,  water  2'7.  The  impure 
varieties,  Rhodonite,  Photizite,  and  Allagite,  contain  varia- 
ble proportions  of  carbonate  of  iron,  lime,  or  manganese, 
beside  alumina.  Becomes  dark  brown  when  heated,  and  fuses 
with  borax  in  the  outer  flame,  giving  a  hyacinth  red  globule. 

Dif.  Resembles  somewhat  a  flesh-red  feldspar,  but  dif- 
fers in  greater  specific  gravity,  in  blackening  on  long  expo- 
sure, and  in  the  glass  with  borax. 

Obs.  Occurs  in  Sweden,  the  Hartz,  Siberia,  and  else- 
where. In  the  United  States  it  is  found  in  masses,  at  Plain- 
field,  and  Cummington,  Mass.  ;  also  abundantly  at  Hinsdale, 
and  on  Stony  Mountain,  near  Winchester,  N.  H. ;  at  Blue 
Hill  Bay,  Me.  The  black  exterior  is  a  more  or  less  pure 
hydrated  oxyd  of  manganese. 

Uses.  Dr.  Jackson  has  suggested  the  use  of  this  ore  for 
1  making  a  violet-colored  glass,  and  also  for  a  colored  glazing 
on  stone  ware.  The  finely  pulverized  mineral,  spread  on 
stone  ware  as  a  paste,  will  afford  a  permanent  glazing, 
which  will  have  a  black  color  if  it  be  of  considerable  thick- 
ness, and  of  a  deep  violet-blue  if  quite  thin.  It  may  be 
used  along  with  the  usual  salt  glazing. 


What  is  said  of  the  ores  of  manganese  ?  What  is  the  appearance 
of  manganese  spar  ?  its  composition  and  blowpipe  characters?  How 
is  it  distinguished  from  feldspar  I  For  what  may  it  be  used  'I 


240  METALS. 

It  receives  a  high  polish  and  is  sometimes  employed  for 
inlaid  work. 

Troostite.  A  silicate  of  iron  and  manganese  occurring  in  six-sided 
prisms  ;  R  on  R=115°.  Also  massive.  Color  dull  greenish  to  reddish- 
brown.  H=5-5.  Gr=4.  From  Franklin,  New  Jersey.  Tephroite 
is  a  variety  of  it. 

Bustamite.  A  silicate  of  manganese  and  lime  occurring  in  spheri- 
cal and  reniform  masses.  H=s6— 6'5.  Gr=3'2.  From  Mexico. 

PYROLUSITE — Binoxyd  of  Manganese. 

Trimetric.  In  small  rectangular  prisms,  more  or  less 
modified.  M  :  M=93°  40' ;  M  :  e=s 
136  50'.  Sometimes  fibrous  and  ra- 
diated or  divergent.  Often  massive 
and  in  reriform  coatings. 

Color  iron-black  ;  streak  black,  un- 
\.  .^    metallic.    H=2— 25.  Gr=4-8— 5-0. 

X c^^          Composition:    essentially  the  bin- 

oxyd  ot  manganese,  consisting  of  oxygen  36,  and  manganese 
44.  With  borax  it  gives  an  amethystine  globule.  It  yields 
no  water  in  a  matrass. 

Dif.  Differs  from  psilomelane  by  its  inferior  hardness, 
and  from  ores  of  iron  by  the  violet  glass  with  borax. 

Obs.  This  ore  is  extensively  worked  in  Thuringia,  Mo- 
ravia,  and  Prussia.  It  is  common  in  Devonshire,  Somerset- 
shire,  and  Aberdeensliire,  in  England.  In  the  United  States 
it  is  associated  with  the  following  species  in  Vermont,  at 
Bennington,  Brandon,  Monkton,  Chittenden,  and  Irasburg ; 
it  occurs  also  in  Maine,  at  Con  way,  and  Plainfield,  in  Mas- 
sachusetts  ;  at  Salisbury,  and  Kent,  in  Conn.,  on  hematite. 

The  name  pyrolusite  is  from  the  Greek  pur,  fire,  and  /wo, 
to  wash,  and  alludes  to  its  property  of  discharging  the  brown 
and  green  tints  of  glass,  for  which  it  is  extensively  used. 

Uses.  Besides  the  use  just  alluded  to,  this  ore  is  exten- 
sively  employed  for  bleaching,  and  for  affording  the  gas  oxy- 
gen to  the  chemist. 

TSILOMELANE. 

Massive  and  botryoidal.  Color  black  or  greenish-black. 
Streak  reddish  or  brownish-black,  shining.  H  =  5—6.  Gr= 
4—4-4. 

Describe  pyrolusite.  What  is  its  constitution  ?  What  are  its  uses  1 
Describe  psitomelane  1  How  does  it  differ  from  pyrolusite. 


MANGANESE  ORES.  241 

Composition  :  essentially  bmox yd  of  manganese  with  one 
per  cent,  of  water,  and  also  some  baryta  or  potassa.  The 
compound  is  somewhat  varying  in  its  constitution.  Before 
the  blowpipe  like  pyrolusite,  except  that  it  affords  water. 

Obs*  This  is  an  abundant  ore,  and  is  associated  usually 
with  the  pyrolusite.  Prof.  Silliman,  jr.,  has  lately  detected 
oxyd  of  cobalt  mixed  with  this  ore.  It  occurs  at  the  differ- 
ent localities  mentioned  under  pyrolusite,  and  the  two  are 
often  in  alternating  layers  ;  it  has  been  considered  only  an 
impure  variety  of  the  pyrolosite.  The  name  is  from  the 
Greek  psilas,  smooth  or  naked,  and  melas1  black. 

Uses.     Same  as  with  pyrolusite. 

Heteroclin  and  marceline  are  similar  ores,  containing  10  to  16  pel 
cent,  of  silica. 

WAD. — Bog  manganese. 

Massive,  reniform  or  earthy  ;  also  in  coatings  and  dendri- 
tic delineations. 

Color  and  streak  black  or  brownish-black.  Luster  dull, 
earthy.  H=l.  Gr=3'7.  Soils. 

Composition.  Consists  of  peroxyd  of  manganese,  in  vary- 
ing proportions,  from  30  to  70  per  cent,  along  with  peroxyd 
of  iron,  20  to  25  per  cent,  of  water,  and  often  several  per 
cent,  of  oxyd  of  cobalt  or  copper.  It  is  a  hydrated  peroxyd, 
mechanically  mixed  with  other  oxyds,  organic  acids  and 
other  impurities,  and  like  bog  iron  ore,  is  formed  in  low  places 
from  the  decomposition  of  minerals  containing  manganese. 
Gives  off  much  water  when  heated,  and  affords  a  violet  glass 
with  borax. 

Obs.  Wad  is  abundant  in  Columbia  and  Dutchess  coun- 
ties, N.  Y.,  at  Austerlitz,  Canaan  Center,  and  elsewhere ; 
also  at  Blue  Hill  Bay,  Dover,  and  other  places  in  Maine  ;  at 
Nelson,  Gilmanton,  and  Grafton,  N.  H.  ;  and  in  many  other 
parts  of  the  country. 

Uses.  May  be  employed  like  the  preceding  in  bleaching, 
but  is  too  impure  to  afford  good  oxygen.  It  may  also  be 
used  for  umber  paint. 

TRIPLITE. — Ferruginous  Phosphate  of  Manganese. 
Massive,  with  cleavage  in  three  directions.     Color  black- 
ish-brown.   Streak  yellowish-gray.     Luster  resinous  ;  near- 
ly or  quite  opaque.     H=5 — 5'5.     Gr=3'4 — 3'8. 

What  is  wad  ?  its  coni|>oeition  ?  its  origin  ?  For  what  may  it  be 
used  ?  What  is  triplite  I 

21 


242  METALS. 

Composition:  protoxyd  of  manganese  32'6,  protoxyd 
iron  31*9,  phosphoric  acid  32'8,  with  some  phosphate  of  lime. 
Fuses  easily  to  a  black  scoria,  before  the  blowpipe  ;  dis- 
solves  in  nitric  acid,  and  gives  a  violet  glass  with  borax. 

Obs.  From  Limoges  in  France.  Rather  abundant  at 
Washington,  Conn.,  and  sparingly  found  at  Sterling,  Mass. 

Heterosite  is  another  phosphate  of  the  oxyds  of  manganese  and 
iron,  of  a  greenish-gray  or  bluish  color.  Contains  41'77  per  cent,  ot' 
phosphoric  acid.  Huraulite  is  a  hydrous  phosphate  of  the  same  oxyds, 
containing  18  per  cent,  of  water  and  38  of  phosphoric  acid.  Occurs 
in  transparent,  oblique,  reddish-yellow  crystals.  Gr=2'27.  From  the 
commune  of  Hureaux,  near  Limoges. 

Hausmannile.  A  sesquioxyd  of  manganese  containing  72' 7  per 
cent,  of  manganese,  when  pure.  Brownish-black  and  submelallic,  oc- 
curring massive  and  in  square  octahedrons  ;  H=5 — 5'5.  Gr=4'7, 
From  Thuringia  and  Alsatia. 

Braunite.  A  protoxyd  of  manganese,  containing  79  per  cent,  of 
manganese  when  pure.  Color  and  streak  dark  brownish-black,  and 
luster  submetallic.  Occurs  in  square  octahedrons  ;  11=6 — 6~5.  Gr= 
4'8.  From  Piedmont  and  Thuringia. 

Manganite.  A  hydrous  seequioxyd  of  manganese.  Occurs  mas- 
sive and  in  rhombic  prisms.  Color  steel-black  to  iron-black.  H=4 — 
4'5.  Gr=4'3 — 4'4.  From  the  Hartz,  Bohemia,  Saxony,  and  Aber- 
deenshire. 

Peloconite  is  an  ore  of  manganese  and  iron,  of  a  bluish-black  color, 
and  liver  brown  streak,  with  a  weak  vitreous  luster.  From  Chili. 

Manganblendc,  or  Alabandine.  A  sulphuret  of  manganese,  of  ani 
iron-black  color,  green  streak,  submetallic  luster.  H=3  5 — 4.  Gr= 
3'9 — 4'0.  Crystals,  cubes  and  regular  octahedrons.  From  the  gold 
mines  of  Nagyag,  in  Transylvania. 

Hauerite  is  a  sulphuret,  containing  twice  the  proportion  of  sulphur  in 
the  last.  Color  reddish-brown  and  brownish-black,  resembling  zinc 
blende.  H=4.  Gr=3'46.  From  Hungary. 

There  is  also  an  arseniuret  of  manganese,  of  a  grayish-white  color, 
and  metallic  luster,  which  gives  off  alliaceous  fumes.  G=5'55.  From 
Saxony. 

Diallogite.  A  carbonate  of  manganese.  Color  rose-red  to  brown- 
ish ;  streak  uncolored.-*  Luster  vitreous,  inclining  to  pearly.  Translu- 
cent to  subtranslucent.  Crystals  rhombohedral.  H=3'5.  Gr=3'59. 
Infusible  alone.  From  Saxony,  Transylvania,  and  the  Hartz.  Also 
from  Washington,  Conn.,  with  triplite. 

GENERAL  REMARKS  ON  THE  ORES  OF  MANGANESE. 

Manganese  is  never  used  in  the  arts  in  the  pure  state  ;  but  as  an  oxyd 
it  is  largely  employed  in  bleaching.  The  importance  of  the  ore  for  thia 
purpose,  depends  on  the  oxygen  it  contains,  and  the  facility  with  which 

On  what  does  the  value  of  manganese  ores  depend  in  the  art  of  bleach- 
ing J 


NICKEL    ORES.  243 

this  gas  is  given  up.  As  the  ores  are  often  impure,  it  is  important 
to  ascertain  their  value  in  this  respect.  This  is  most  readily  done  by 
heating  gently  the  pulverised  ore  with  muriatic  acid,  and  ascertaining 
the  amount  of  chlorine  given  off.  The  chlorine  may  be  made  to  pass 
into  milk  if  lime,  to  form  a  chlorid,  and  the  value  of  the  chlorid  then 
.•cording  to  the  usual  modes.  The  amount  of  chlorine  derived 
from  a  Driven  quantity  of  muriatic  acid  depends  not  only  on  the  amount 
ot  oxygen  in  the  ore,  but  also  on  the  presence  or  absence  of  baryta  and 
such  other  earths  as  may  combine  with  this  acid.  The  binoxyd  of  man- 
ganese when  pure,  afibrds  18  parts  by  weight  of  chlorine,  to  22  parts 
tot  the  oxyd  ;  or  23£  cubic  inches  of  gas  from  22  grains  of  the  oxyd. 
The  bes-'t  ore  should  give  about  three-fourths  its  weight  of  chlorine,  or 
about  7000  cubic  inches  to  the  pound  avoirdupois. 

The  chlorine  for  bleaching  is  used  commonly  in  combination  with 
lime.  To  make  the  chlorid  of  lime,  the  chlorine  is  generally  obtained 
either  through  the  action  of  muriatic  acid  on  the  ore,  (3  to  4  parts  by 
iweight  of  the  former,  to  1^  of  the  latter,)  or  more  commonly  by  mix- 
jmg  1  part  of  the  ore  with  \\  parts  of  common  salt,  2  or  2^  parts  of  con- 
centrated sulphuric  acid,  and  as  much  water.  As  the  chlorine  passes 
ioff,  it  is  conveyed  into  chambers  containing  slaked  lime,  by  which  it  is 
absorbed. 

Manganese  is  also  employed  to  give  a  violet  color  to  glass.  The 
fenlphate  and  the  chlorid  of  manganese  are  used  in  calico  printing.  The 
sulphate  gives  a  chocolate  or  bronze  color. 

The  best  beds  of  manganese  ores  in  the  United  States,  which  have 
been  opened,  are  at  Brandon,  Chittenden,  and  Irasburg,  Vt. 

6.     CHROMIUM. 

The  ores  of  chromium  are  the  chromates  of  lead  and 
bhromic  iron,  which  are  described  under  Lead  and  Iron. 
|There  is  also  a  native  chromic  ochre,  supposed  to  consist  of 
silica  chromic  acid,  alumina,  and  iron.  Wolchonskoite  is  an 
allied  mineral.  MHoschine  or  Serbian  is  considered  a  chro- 
piiferous  clay.  r 

7.    NICKEL. 

The  ores  of  nickel,  excepting  one  or  two,  have  a  metallic 
lister,  and  pale  color ;  their  specific  gravity  is  between  3 
md  8,  and  hardness  mostly  between  5  and  6,  (in  one,  about 

8.)     They  resemble  some  cobalt  ores,  but  do  .lot  like  {hem 

feive  a  deep  blue  color  with  borax. 


I    How  is  manganese  used  1     For  what  other  purpose  is  man£ 
tised  ?     What  is  said  of  the  ores  of  chromium  ]     What  is  said  o$  the 
ores  of  nickel  ? 


244  HETA1S. 


COPPER  NICKEL — Arsenical  Nickel. 

Hexagonal,  Usually  massive.  Color  pale  copper-red ; 
streak  pale  brownish-red.  Luster  metallic.  Brittle.  H=5 
— 5-5-  Gr=7-3— 7-7. 

Composition  :  nickel  44,  and  arsenic  54  ;  sometimes  part 
of  the  arsenic  is  replaced  by  antimony.  Gisres  off  arsen- 
ical (alliaceous)  fumes  before  the  blowpipe,  and  fuses  to  a 
pale  globule,  which  darkens  on  exposure.  Assumes  a  green 
coating  in  nitric  acid,  and  is  dissolved  in  aqua-regia. 

Dif.  Distinguished  from  iron  and  cobalt  pyrites  by  its 
pale  reddish  shade  of  color ;  also  from  the  former  by  its  ar- 
senical fumes,  and  from  the  latter  by  not  giving  a  blue  color 
with  borax.  None  of  the  ores  of  silver  with  a  metallic  lus- 
ter have  a  pale  color,  excepting  native  silver  itsel£ 

O6*.  Accompanies  cobalt,  silver,  and  copper  ores  m  the 
mines  of  Saxony,  and  other  parts  of  Europe  ;  also  sparingly 
in  Cornwall. 

It  is  found  at  Chatham,  Conn.,  in  gneiss,  associated  with 
smaltine  and  a  tin- white  ore  of  cobalt,  where  it  has  been 
mined,  but  with  only  moderate  proceeds. 

White  nickel  is  a  second  arsenical  ore  ;  it  has  a  tin-white  color,  and 
contains  20  to  28  per  cent,  of  nickel,  with  70  to  72  of  arsenic.  Crys- 
tals cubic.  From  ReLchelsdorf,  in  Hesse- Cassel,  and  Schneeberg,  in 
Saxony.  Cloanthite  is  this  «pecies. 

Placsdinc  is  a  third  arsenical  ore,  containing  57  per  cent,  of  nickel. 
Its  crystals  are  tabular,  secondaries  to  an  oblique  rhombic  prism.  Ils 
color  is  bronze-yellow.  H=5 — 55.  Gr=7'9 — 8'1.  From  Muse n,  in 
Prussia. 

Nickel  glance  is  a  fourth  arsenical  ore,  occurring  in  cubes  and  mas- 
sive. Color  silver-white  to  steel-gray..  Contains  28  to  30  per  cent,  of 
nickel  with  arsenic  and  sulphur.  H=5  5.  Gr=6'l.  From  Helsing- 
Jand,  in  Sweden,  and  also  in  the  Hartz.  Also  at  Schladining,  in  Aus- 
tria, containing  38  per  cent,  of  nickel,  and  haying  the  speeilie  gravity 
6-6—6-9. 

Amoibiie  is  a  fifth  arsenical  ore,  containing  14  per  cent,  of  sul- 
phur and  10  per  cent,  more  nickel  than  nickel  glance..  Crystals  mono- 
metric.  Gr=6-Q8.  From  Lichtenberg,  in  the  Fichtelgebirge. 

Nickel  Stibine.  An  antknoniai  sulphuret,  called  sometime?  Nickel- 
ifxrous  antimony  or,(.,  containing  25  to  28  per  cent,  of  niekei.  Color 
steel-gray,  inclining  to  sihrer-white.  In  cubical  crystals  and  also  mas- 
sive. H=5 — 55-  Gr=6'45.  From  (he  Ducby  of  Nassau. 

Aixtimou.i&l  nickel.     Contains  29  per  cent,  of  nickel  and  no  sulphur. 

What  is  the  crystallization  and  appearance  of  copper  nickel  1  of 
what  does  it  consist?  How  is  it  distinguished  from  iron  and  cobalt  py- 
rites 1  how  from  silver  ores  1  Where  tlotis  k  occur  I 


NICKEL    ORES.  245 

It  has  a  pale  copper-red  color,  inclining  to  violet.  H=5'5 — 6.  Gr= 
7'5.  Crystals  hexagonal.  From  the  Andreasberg  mountains. 

Nickel  pyrites,  or  Capillary  pyrites.  A  brass-yellow  sulphuret  of 
nickel,  occurring  usually  in  delicate  papillary  forms  ;  also  in  rhombohe- 
dral  crystals.  Gr=5  28.  Contains  64  3  per  cent,  of  nickel.  From 
Bohemia,  Saxony,  and  Cornwall.  A  sulphuret  of  iron  and  nickel,  of 
a  light  bronze-yellow,  has  been  reported  from  southern  Norway.  It  con- 
tains 22  per  cent,  of  nickel.  Gr=4'6.  A  similar  compound,  resem- 
bling iron  pyrites,  containing  9  percent,  of  nickel,  has  been  observed  at 
Mine  La  Motte,  Missouri,  by  Wm.  H.  King.  Still  another  sulphu- 
ret (called  bismuth  nickel,)  contains  14  per  cent,  of  bismuth,  with  40.7 
of  nickel.  Color  light  steel-gray  to  silver-white  ;  often  tarnished  yel- 
lowish. H=4'5.  Gr=5-13.  From  the  district  of  Altenkirchen,  Prussia. 

Nickel  green.  An  arsenate  of  nickel,  containing  36'2  per  cent,  of 
oxyd  of  nickel.  Color  fine  apple-green.  Occurs  with  other  nickel 
ores  in  Dauphiny,  Prussia,  and  elsewhere.  It  is  found  with  copper 
nickel  at  Chatham,  Conn. 

GREEN    HYDRATE    OF    NICKEL. 

Incrusting,  minute  globular  or  stalactitic.  Color  bright 
emerald  green.  Luster  vitreous.  Transparent  or  nearly 
so.  H=3— 3-25.  Gr=3-05. 

It  is  a  hydrate  of  nickel,  containing  38*50  per  cent,  of  wa- 
ter. Infusible  before  the  blowpipe  alone,  but  loses  its  color. 

Obs.  Occurs  with  chromic  iron  and  carbonate  of  magne- 
sia, on  serpentine,  in  Lancaster  county,  Pennsylvania. 

An  earthy  oxyd  of  nickel  and  sulphuret  occurs  with  black 
cobalt,  at  Mine  la  Motte,  Missouri. 

Pimelite  is  a  clay  colored  by  green  oxyd  of  nickel.  Klap- 
roth  found  15*6  per  cent,  in  one  specimen.  Quartz  is  some- 
times colored  by  nickel.  Chyroprase  is  a  chalcedony  thus 
colored. 

GENERAL  REMARKS  ON  NICKEL  AND  ITS  ORES. 

The  nickel  of  commerce  is  obtained  mostly  from  the  copper  nickel, 
or  from  an  artificial  product  called  speiss,  (an  impure  arseniuret,)  de- 
rived from  roasting  ores  of  cobalt  with  which  arseniuretted  nickel  ores 
are  mixed.  The  ores  are  no  where  very  abundant,  and  the  most  pro- 
ductive are  those  of  Saxony  and  Germany. 

Nickel  also  occurs  in  meteoric  iron,  forming  an  alloy  with  the  iron, 
which  is  characteristic  of  most  meteorites.  The  proportion  sometimes 
amounts  to  15  per  cent.  The  great  Texas  meteorite,  now  in  the  Yale 
College  collections,  contains  8'8  to  9- 7  per  cent,  of  this  metal. 

Nickel  is  obtained  in  the  pure  state  from  the  speiss,  by  the  following 


Describe  the  green  hydrate  of  nickel.     What  is  pimelite?     What 
ores  afford  the  nickel  of  commerce  1     Where  else  is  it  found  ? 

21* 


246  METALS. 

process,  proposed  by  Wohler :  1  part  of  the  ore  is  fused  with  3  of 
pearlash  and  3  of  sulphur.  The  arsenic  forms  a  soluble  compound 
with  the  sulphur  and  potash,  and  the  nickel  an  insoluble  sulphuret, 
This  is  well  washed  with  water  and  dissolved  in  nitric  acid  ;  and  the 
solution,  after  any  lead,  copper,  or  bismuth,  that  may  be  present,  have 
been  precipitated  by  a  current  of  sulphuretted  hydrogen,  is  precipitated 
by  caustic  or  carbonated  potash  or  soda.  The  washed  precipitate  is 
now  acted  on  by  an  excess  of  oxalic  acid,  which  forms  with  the  peroxyd 
of  iron,  that  is  generally  present,  a  soluble,  and  with  the  oxyd  of  nickel 
an  insoluble,  oxalate,  which  of  course  includes  any  cobalt  that  the  ore 
may  have  contained.  The  oxalate  is  now  dissolved  in  an  excess  of  am- 
monia, and  the  solution  exposed  to  the  air.  As  the  ammonia  escapes, 
the  nickel  is  deposited  as  an  insoluble  double  oxalate,  while  the  cobalt 
remains  dissolved  as  a  soluble  double  oxalate  of  the  metallic  oxyd  with, 
ammonia.  The  nickel  salt,  being  ignited,  leaves  an  oxyd  which  may 
be  reduced  by  heating  with  charcoal ;  or  it  may  be  dissolved  in  acid  and 
again  converted  into  oxalate,  which  this  time  is  free  from  cobalt  and 
appears  as  an  apple-green  powder.  The  oxalate  of  nickel,  being  well 
washed,  dried  and  ignited  in  a  closed  crucible,  with  an  aperture  for  the 
escape  of  gas,  leaves  metallic  nickel,  which,  if  the  heat  be  very  intense, 
is  fused  to  a  button.  Its  color  is  between  that  of  silver  and  tin. 

As  nickel  does  not  rust  or  oxydize,  (except  when  heated,)  it  is  supe~ 
rior  to  steel,  for  the  manufacture  of  many  philosophical  instruments. 

An  alloy  of  copper,  nickel,  and  zinc,  has  been  much  used  for  various 
purposes,  under  the  name  of  German  silver,  or  argentane.  Good  Ger- 
man silver  consists  of  copper  8  parts,  nickel  3,  zinc  3J.  An  inferior 
article  is  made  of  copper  8,  nickel  2,  zinc  3£.  Below  the  proportion 
of  nickel  last  stated,  the  alloy  approaches  pale  brass  and  tarnishes 
readily,  while  the  better  kind  has  the  appearance  of  silver,  and  retains 
well  its  polish.  It  is,  however,  easily  distinguished  from  silver  by  a 
somewhat  greasy  feel. 

But  "  German  silver"  is  not  a  very  recent  discovery.  In  the  reign 
of  William  III,  an  act  was  passed  making  it  felony  to  blanch  copper  in 
imitation  of  silver,  or  mix  it  with  silver  for  sale.  '*  White  copper"  has 
long  been  used  in  Saxony  for  various  small  articles  ;  the  alloy  employed 
is  stated  to  consist  of  copper  88' 00,  nickel  8' 75,  sulphur  with  a  little 
antimony  0  75,  silex,  clay  and  iron,  T75.  A  similar  alloy  is  well  known 
in  China,  and  is  smuggled  into  various  parts  of  the  East  Indies,  where 
it  is  called  packfong.  It  has  been  sometimes  identified  with  iht 
Chinese  tutenugue.  M.  Meurer  analyzed  the  white  copper  of  China, 
and  found  it  to  consist  of  copper  G5'24,  zinc  19  52,  nickel  13,  silver  2'5: 
with  a  trace  of  cobalt  and  iron.  Dr.  Fyfe  obtained  copper  40'4,  nickel 
31-6,  zinc  25.4,  and  iron  2' 6.  It  has  the  color  of  silver,  and  is  remark- 
ably sonorous.  It  is  worth  in  China  about  one-fourth  its  weight  of  sil- 
ver, and  is  not  allowed  to  be  carried  out  of  the  empire. 

Nickel  alloyed  with  iron,  as  in  meteoric  iron,  renders  it  less  liable  to 
rust  ;  but  with  steel  the  tendency  to  rust  is  increased. 

Articles  are  now  plated  with  nickel,  by  galvanic  precipitation  from 
the  sulphate. 


How  is  nickel  obtained  from  the  ore  ?     For  what  is  nickel  used  1 
What  is  German  silver  ?     What  is  the  Chinese  packfong? 


8.    COBALT. 

Cobalt  has  not  been  found  native.  The  ores  of  cobaft 
having  a  metallic  luster,  vary  in  specific. gravity  from  6'2  to 
7'2  ;  and  -the  color  is  nearly  tin- white  or  pale  steel-gray,  in- 
i  dining  to  copper-red.  Tlie  ores  wi&out  a  metallic  luster 
have  a  clear  red  or  reddish  color,  and  specific  'gravity  of 
nearly  «S.  The  ores  are  remarkable  fjr  giving  a  deep  blue 
color  to  glass  of  borai,  even  when  tke  proportion  of  cobalt 
is  smalk 

SMALTINE. — Tin^whvte  Cobalt, 

Monometric.  Occurs  in  octahedrons,  cubes,  and  dodeca* 
Jiedrons,  more  or  less  modified,  {See  figs.  1,  2,  ^,  page  25, 
and  32,  37,  page  36.)  Cleavage  octahedral,  somewhat  dis- 
tinct. Also  reticulated ;  often  massive. 

Color  tin-white,  sometimes  inclining  to  steel-gray.    Streak 
grayish-black.     Fracture  granular  and  uneven.     H=5*3— 
j  <ir=6-4— 7-2. 

Composition :  essentially  cobalt  and  arsenic ;  the  cobalt 
'  varies  from  18  to  23 -5  per  cent,  and  the  arsenic  from  69  to 
I  79  per  cent.     A  variety  contains  9  to  14  per  cent,  of  cobalt 
I  and  is  called  r&diated  white  cobalt.;   another  variety  con- 
tains bismuth. 

Gives  off  arsenical  fames  in  a  candle.     Colors  borax  and 

;  other  fluxes  blue,  and  affords  a  pink  solution  with  nitric  acid. 

Dif.     The  arsenical  cobalts   are  at  once  distinguished 

from  mispickel  or  white  iron  pyrites,  by  the  blue  color  they 

give  with  borax ;  and  also  by  their  crystals  and  specific 

gravity. 

Obs.  Usually*  in  veins  with  ores  of  cobalt,  silver,  and 
,  copper.  Occurs  in  Saxony,  especially  at  Schneeburg  ;  also 
\  in  Bohemia,  Hessia,  and  Cornwall. 

In  the  United  States  it  is  found  in  gneiss  with  copper 
nickel,  at  Chatham,  Conn. 

Cobaltinc.     This  is  another  arsenical  ore  of  cobalt,  containing  sul- 
phur as  well  as  arsenic.     Color  silver-white,  inclining  to  red.     Con 
tains  33  to  37  per  cent,  of  cobalt.     Forms  of  crystals,  figures  42,  4P 
1   page  37.     From  Sweden,  Norway,  Siberia,  and  Cornwall.     The  mos 

What  is  said  of  the  ores  of  cobalt  ?  Describe  tin-white  cobalt  1 
What  is  its  composition  ?  its  blowpipe  characters  ?  How  is  it  distin- 
guished from  mispicke)  and  white  iron  pyrites? 


248  METALS, 

productive  mines  are  those  of  Wehna,  in  Sweden,  which  were  ftrsl 
opened  in  1809. 

Cobalt  pyrites  is  a  snlphuret  of  cobalt,  of  a  pale  reddish  or  steel-gray 
color.  H=5'5.  Gr=6'3 — 6'4.  Crystals  cubic.  From  Sweden,  and 
also  Prussia ;  also  Mine  La  Motte,  Missouri. 

Another  sulphuret  of  cobalt,  with  a  less  proportion  of  sulphur  thai* 
in  the  last,  has  been  observed  in  Hindostan.  Color  steel-gray,  a  little 
yellowish. 

EARTHY  COBALT. — Black  oxyd  of  Cobalt. 

Earthy,  massive.  Color  black  or  blue -black.  Soluble? 
in  muriatic  acid,  with  an  evolution  of  fumes  of  chlorine. 

Obs.  Occurs  in  an  earthy  state  mixed  with  oxyd  of  man- 
ganese, and  in  Missouri  has  been  mistaken  for  black  oxyd 
of  copper.  It  is  quite  abundant  at  Mine  La  Motte,  Missouri, 
and  also  near  Silver  Blu-ff,  South  Carolina.  The  analyses 
vary  in  the  proportion  of  oxyd  of  cobalt  associated  with  the 
manganese,  as  the  compound  is  a  mere  mixture.  Sulphuret 
of  cobalt  occurs  with  the  oxyd.  The  Carolina  ores  afforded 
Dr.  J.  L.  Smith,  oxyd  of  cobalt  24,  oxyd  of  manganese  76, 
The  ore  from  Missouri,  as  analyzed  by  Prof.  Silliman,  Jr., 
afforded  40  per  cent,  of  oxyd  of  cobalt,  with  oxyds  of  nickel, 
manganese,  iron  and  copper.  It  has  also  been  detected 
with  hematite,  in  Chester  Ridge,  Pa. 

This  ore  has  been  found  abroad  in  France,  Germany, 
Austria,  and  England,  but  much  of  it  contains  very  little 
oxyd  of  cobalt. 

Uses.  The  ore  of  Missouri  is  exported  to  England  in  large 
quantities,  and  there  purified  and  made  into  smalt,  for  the  arts. 

COBALT  BLOOM. — Arsenote  of  cobalt. 

Monoclinate.  In  oblique  crystals  having  a  highly  perfect 
eleavage  and  foliated  structure  like  mica.  Laminae  flexible 
in  one  direction.  Also  as  an  incrustation,  and  in  reniform 
shapes,  sometimes  stellate. 

Color  peach  and  crimson  red,  rarely  grayish  or  greenish  ; 
streak  a  little  paler,  the  powder  dry  lavender  blue.  Lus- 
ter of  laminae  pearly  ;  earthy  varieties  without  luster.  Trans- 
parent to  subtranslucent.  H  =  l*5 — 2.  Gr=2'95. 

Composition :  oxyd  of  cobalt  39*2,  arsenic  acid  37'9,  wa- 


What  is  said  of  the  black  oxyd  of  cobalt  1     What  is  the  appearance 
and  structure  of  cobalt  bloom  1  of  what  does  it  consist  1 


COBALT    (TEES.  249 

^^^  Gives  arsenical  fames  when  heated,  .and  fuses  ; 

yields  a  blue  glass  with  borax. 

The  earthy  ore  as  sometimes  called  peach  blossom  ore, 
-from  its  color  ;  and  also  red  cobalt  ochre. 

Dif.  Jlesonibles  red  antimony,  foul  that  species  wholly 
'volatilizes  "before  the  blowpipe.  From  red  copper  ore  it  dit 
frrs  in  giving  a  "blue  glass  with  borax;  moreover  the  color 
of  the  copper  ore  is  more  sombre, 

Obs.  ^Occurs  with  ores  of  lead  and  sliver,  and  other  co- 
balt ores.  Schneeberg,  in  Saxony,  Saalfield  in  Thuringia, 
and  Riegels-JorfJ  in  Hessia,  are  noted  European  localities. 
It  is  found  ako  in  Dauphiny,  Cornwall,  and  Cumberland. 
Occurs  in  fhe  U.  States,  at  Mine  La  Motte,  Missouri. 
Uses.  Valuable  as  an  ore  of  cobalt,  when  abundant. 

Rostlitf.  A  Fose-fedtmineral,  related  to,  if  not  identical  with,  co- 
Ibalt  bloom. 

Arseniic  of  cobalt  is  a  compound  of  arsenous  acid  and  oxyd  of -cobalt, 
and  restlts  fpomthe  decomposition  of  other  cobalt  ores. 

Sulphate  of  cobalt,  >or<CobaU  vitriol.  It  has  a  flesh  or  rose-red  tint, 
and  astringent  taste.  .Consists  -of  salphucic  acid,  oxyd  of  cobalt  and 
water. 

"GENERAL  REMARKS  ON    COBALT    AND  ITS  'OHES. 

The  two  arsenical  oresx>f  cobalt  afford  the  greater  part  of  the  cobalt 
of  commerce.  The  earthy  *rxyd  is  so  -abundant  in  the  United  States, 
ahat  it  promises  to  be  a  profitable  souroe  of  this  metal.  Cobalt  is  never 
employed  in  the  arts  in  a  metallic  state,  as  its  alloys  arelmttle  and  un- 
important, k  is  chiefly  used  for  painting  porcelain  and  pottery,  and 
is  required ibr  thispurpose  in  the  stateof  an'Oxyd,'Or  the  silicated  oxyd 
called  smalt  and  azure. 

Cooalt  oomes  from  -Germany  .mostly  in  die  .fiilicated  xjondition.  The 
•zajfre  is  prepared  by  calcining  the  ores  of  cobalt  in  a  reverberatory  fur- 
«ace  ;  the  sulphur  and  arsenic  are  thus  volatilized,  and  an  impure  oxyd 
remaias,  which  is  nextanixed  and -heated  wkh  aibout  twice  its  weight 
of  finely  powdered  flinte. 

By  another  process  the  ore  is  pulverized  and  roasted,  to  expel  the 
•greater  part  of  the  arsenic  ;  --a  sulphate  is  then  formed  by  heating  for 
an  hour -with  concentrated  sulphuric  acid-  The  sulphate  is  dissolved  in 
water,  and  a  solution  of -carbonate  of  potash  added  to  separate  the  iron-.; 
-«nd  when  the  biue<;olor  of  the  <xibalt  begins  to  be  thrown  down,  the 
supernatant  liquid  is  decanted  and  .filtered,  and  the  cobalt  is  precipitated 
oy  means  of  a  sofatifn  of  sweated  potash,  (prepared  ;by  heating  to- 
gether 10  parts  of  potash,  15  of  finetp  pulverized  jquartz,  and  I  of  char- 
coal, and  afterwards  treating  the  melted  mass  with  boiling  water.)  The 
*i:ieate  of  cobalt  thus  prepared  is  .said  >to  foe  superior  to  that  procured 

How  does  cobalt  bloom  difler  from  red  antimony  ?     From  what  ores 
i«  the  cdbalt  of  commerce  obtained  ?     For  what  is  cobalt  used  1     la 
condition  is  it  imported  from  Germany  ?     What  is  zaffrfi  1 


!  Is  th< 


250  METALS, 

in  any  other  way,  for  staining  porcelain,  or  for  the  manufacture  of  bltr* 
glass. 

Smalt  and  azure,  which  have  a  rich  blue  color,  are  made  by  fusing 
zaffre  with  glass ;  or  by  calcining  a  mixture  of  equal  parts  of  roasted 
cobalt  ore,  common  potash,  and  ground  glass-.  The  zaffre  is  used  for 
coloring  glass,  and  for  painting  enamel  and  pottery  ware.  The  arsenic 
volatilized  in  the  above  process  is  condensed  in  chambers ;  it  consti- 
tutes the  greater  part  of  the  arsenic  of  commerce.  The  separation  of 
the  nickel  from  ores  rich  in  this  metal,  is  sometimes  effected  by  exposing 
the  moistened  ore  to  the  atmosphere.  The  nickel  is  unaltered,  while 
the  other  metals  aie  oxydized. 

The  annual  yield  of  zaffre  or  smalt,  in  Saxony,  amounts  to  8000 
«wt.  ;  in  Bohemia,  mainly  from  Schlackenwald,  4000  cwt.  ;  m  the 
Reisengebirge,  in  Prussia,  600  ewt.  :  aft  Kongsberg,  in  Norway, 
4000  cwt. 

9.     ZINC. 

Zinc  occurs  in  combination  with  sulphur,  oxygen,  silica, 
carbonic  acid,  and  sulphuric  acid-  It  is  also  found  in  com- 
bination with  alumina,  constituting  one  variety  of  the  spe- 
cies spinel. 

The  ores  of  zinc  are  infusible,  or  very  nearly  so ;  but 
they  yield  on  charcoal,  with  more  or  less  difficulty,  white 
fumes  of  the  oiyd  of  zinc.  Specific  gravity  below  4*5. 

BLENDE. — Sulphuret  of  Zinc. 

Monometrie..     In  dodecahedrons,  octahedrons*  and  other 
allied  forms,  with  a  perfect  dodecahedral  cleavage.     Also 
massive ;  sometimes  fibrous. 

Color  wax-yellow,  brownish- 
yellow,  to  black,  sometimes  green 
or  red ;  streak  white,  to  red- 
dish-brown. Luster  resinous  or 
waxy,  and  brilliant  on  a  cleavage 
face  ;  sometimes  submetallic. — 

Transparent  to  subtranslucent.  Brittle.    H  =  3-5 4.    Gr  = 

4*0 — 4*1.  Some  specimens  become  electric  with  friction,  and 
give  off  a  yellow  light  when  rubbed  with  a  feather. 

Composition  :  zinc  66-72,  sulphur  33-28.  Contains  fre- 
quently a  portion  of  sulphuret  of  iron  when  dark  colored  ; 

What  are  smalt  and  azure  I  How  are  they  used  in  porcelain  paint- 
ing? What  is  said  of  the  ores  of  zinc  ?  What  is  the  crystallization 
of  blende.  What  are  its  luster,  color*  and  other  physical  characters  ? 
Of  what  does  it  consist  I 


ZIXC    ORES.  251 

often  also  1  or  2  per  cent,  of  sulphuret  of  cadmium,  espe- 
cially the  red  variety.  Infusible  alone  and  with  borax. 
Dissolves  in  nitric  acid,  emitting  sulphuretted  hydrogen. 
Strongly  heated  on  charcoal  yields  fumes  of  zinc. 

Dif.  This  ore  is  characterized  by  its  waxy  luster,  per- 
fect cleavage,  and  infusibility.  Some  dark  varieties  look  a 
little  like  tin  ore,  but  their  cleavage  and  inferior  hardness 
distinguish  them;  and  some  clear  red  crystals  which  re- 
semble garnet  are  distinguished  by  the  same  characters  and 
also  by  their  infusibility. 

Obs.  Occurs  in  rocks  of  all  ages,  and  is  associated  gen- 
erally with  ores  of  lead  ;  often  also  with  copper,  iron,  tin, 
and  silver  ores.  The  lead  mines  of  Missouri  and  Wiscon- 
sin,  afford  this  ore  abundantly.  Other  localities  are  in 
Maine,  at  Lubec,  Bingham,  Dexter,  Parsonsfield  ;  in  New 
Hampshire,  at  Eaton,  Warren,  Haverhill,  Shelburne  ;  in 
Vermont,  at  Thetford  ;  in  Massachusetts,  at  Sterling,  South- 
ampton, and  Hatfieid  ;  in  Connecticut,  at  Brookfield,  Berlin, 
Roxbury,  and  Monroe  ;  in  New  York,  at  the  Ancram  lead 
mine,  the  Wurtzboro  lead  vein,  at  Lockport,  Root,  2  miles 
s.  E.  of  Spraker's  basin,  in  Fowler,  at  Clinton  ;  in  Pennsyl- 
vania, at  the  Perkiomen  lead  mine  ;  in  Virginia,  at  Austin's 
lead  mine,  Wythe  county  ;  in  Tennesse,  near  Powell's  River, 
and  at  Haysboro, 

This  ore  is  the  Black  Jack  of  miners, 

Uses.  Blende  is  a  useful  ore  of  zinc,  though  more  diffi- 
cult of  reduction  than  calamine.  By  its  decomposition, 
(like  that  of  pyrites,)  it  affords  sulphate  of  zinc  or  white 
vitriol. 

RED  ZINC  ORE. — Red  oxyd  of  Zinc. 

Trimetric.  Usually  in  foliated  masses,  or  in  disseminated 
grains  ;  cleavage  eminent,  nearly  like  that  of  mica,  but  the 
laminae  brittle,  and  not  so  easily  separable. 

Color  deep  or  bright  red ;  streak  orange-yellow.  Luster 
brilliant,  subadamantine.  Translucent  or  subtranslucent. 
H=4— 4-5.  Gr=5-4— 5-56. 

Composition  :  ore  of  New  Jersey,  oxyd  of  zinc  93-5,  pro- 
toxyd  of  manganese,  5-5,  peroxyd  of  iron  0-4,  (Hayes.)  In- 

What  is  the  action  of  zinc  blende  before  the  blowpipe  ?  How  is  it  dis- 
tinguished ?  How  do^s  it  occur  ?  What  is  the  appearance  of  red  ziuc 
ore  ?  its  composition  ? 


252 

fusible  alone,  but  yields  a  yellow  transparent  glass  with  fccr-* 
rax.  Dissolves  in  nitric  acid,  without  effervesence. 

Dif.  Resembles  red  stilbitey  bst  distinguished  by  its  in- 
fusibility  and5  also  by  its  mineral  associations. 

Obs.  Occurs  with  Franklfrute  at  Franklm  and  Sterling, 
N.  J. 

Uses.  A  good  ore  of  zinc  whefi  abundant,  and  easily  re- 
duced. It  may  be  readily  and  economically  converted  into- 
sulphate  of  zinc,  or  white  vitriol. 

Voltziie.  A  compound  of  su£phuret  and  oxycf  of  zfnc.  Occurs  in 
implanted  globules  of  a  dirty  rose-rerf  coior,  wish  a  pearly  luster  en  » 
eleavage  surface.  Frofii  France. 

SULPHATE  OF  ZINC.—  -  White  VitrioL 

Trimetric.  Cleavage  perfect  in  one  direction.  Crystal! 
rhombic  prisms,  of  $0°  42'. 

Color  white.  Luster  vitreous.  Easily  soluble  ;  taste  as- 
tringent metallic,-  and  nauseous.  Brittle.  H^=2—  2*5.-— 


Composition  /  oxyd  of  zinc  28-00,  sulphuric  acid  27'97, 
tyater  43"94r  Gives  off  fumes  of  zinc  when  heated  on  char*: 
coal,  which  cover  the  coal. 

Obs.  Results  from  the  decomposition  of  blende.  Occurs  | 
in  the  Hartz,  in  Hungary,  in  Sweden,  and  at  Holywell  in 
Wales. 

Uses.  Sulphate  of  zfnc  is  extensively  employed  hi  medi-l 
cine  and  dyeing.  For  these  purposes  it  is  prepared  to  a  large 
extent  from  blende,  by  decomposition  Ifke  pyrites,  though  ' 
this  affords,  owing  to  its  impurities,  an  impure  sulphate.  It; 
is  also  obtained  by  direct  combination  of  zinc  with  sulphuric 
acid  ;  zinc  is  exposed  to  the  action  of  dilute  sulphuric  acid,  and 
the  solution  obtained  is  then  evaporated  for  crystallization. 
The  red  oxyd  of  zinc,  of  New  Jersey,  may  become  an  abun- 
dant source  of  this  salt. 

White  vitriol,  as  the  term  is  used  in  the  arts,  is  one  form 
of  sulphate  of  zinc,  made  by  melting  the  crystallized  sulphate, 
and  agitating  till  it  cools  and  presents  an  appearance  like 
loaf  sugar. 


How   does  it  differ  from  red  siilhite  ?    For  what  Tnay  it  be 
What  is  the  appearance  and  lastr  of  white  vitriol  ?     Of  what  does  it 
consist  ?     How  is  it  formed  ?     For  what  is  it  u?ed  ? 


ZINC    ORES.  253 

CALAMINE. — Carbonate  of  Zinc. 

Rhombohedral.  R  :  R  =  107D  40'.  Cleavage  rhombo- 
hedral,  perfect.  Massive  or  incrusting  ;  reniform  and  stal- 
actitic. 

Color  impure  white,  sometimes  green  or  brown ;  streak 
uncolored.  Luster  vitreous  or  pearly.  Subtransparent  to 
translucent.  Brittle.  H  =  5.  Gr  =  4'3 — 4*45. 

Composition :  oxyd  of  zinc  64'54,  (four-fifths  of  which  is 
pure  zinc,)  and  carbonic  acid  35'46.  Often  contains  some 
cadmium.  Infusible  alone  before  the  blowpipe,  but  carbonic 
acid  and  oxyd  of  zinc  are  finally  vaporized.  Effervesces  in 
nitric  acid.  Negatively  electric  by  friction. 

Dif.  The  effervescence  with  acids  distinguishes  this 
mineral  from  the  following  species ;  and  the  hardness,  diffi- 
cult fusibility,  and  the  zinc  fumes  before  the  blowpipe,  from 
the  carbonate  of  lead  or  other  carbonates. 

Obs.  Occurs  commonly  with  galena  or  blende,  and  usu- 
ally in  calcareous  rocks.  Found  in  Siberia,  Hungary,  Sile- 
sia ;  at  Bleiberg  in  Carinthia  ;  near  Ak-la.Chapelle  in  the 
Lower  Rhine,  and  largely  in  Derbyshire  and  elsewhere  in 
England.  In  the  United  States,  it  is  abundant  at  Vallee's 
Diggings  in  Missouri,  and  at  other  lead  "  diggings"  in  Iowa 
and  Wisconsin  ;  also  in  Claiborne  county,  Tenn.  Sparingly 
also  at  Hamburg,  near  the  Franklin  furnace,  N.  J. ;  at  the 
Perkiomen  lead  mine,  Pa.,  and  at  a  lead  mine  in  Lancaster 
county  ;  at  Brookfield,  Conn. 

Zinc  bloom  is  an  earthy  carbonate  of  zinc,  containing  69  per  cent,  of 
oxyd  of  zinc,  and  15  of  water.  From  Bleiberg,  Carinthia. 

ELECTRIC    CALAMINE. Silicate  of  ZlHC. 

Trimetric.  In  modified  rhombic  prisms,  the  opposite  ex- 
tremities with  unlike  planes.  M  :  M  =  103D  53'.  Cleavage 
perfect  parallel  to  M.  Also  massive  and  incrusting,  mammil- 
lated  or  stalactitic. 

Color  whitish  or  white,  sometimes  bluish,  greenish,  or 
brownish.  Streak  uncolored.  Transparent  to  translucent. 
Luster  vitreous  or  subpearly.  Brittle.  H=4*5 — 5.  Gr  = 
3*35 — 3-45.  Pyro-electric. 

What  is  the  usual  appearance  of  calamine  1  What  is  its  constitution 
and  the  effects  before  the  blowpipe  I  What  effect  is  produced  by  fric- 
tion 1  What  are  distinguishing  characteristics?  How  does  it  occur ? 
What  is  electric  calamine  ? 

22 


254  METALS* 

Composition:  silica  26-2,  oxyd  of  zinc  66-4,  water  7*4, 
Before  the  blowpipe  it  slowly  intumcsces  and  emits  a  green 
phosphorescent  light ;  but  alone  it  is  infusible.  Forms  a  clear 
glass  with  borax.  In  heated  sulphuric  acid  it  dissolves,  and 
the  solution  gelatinizes  on  cooling. 

Dif.  Differs  from  carbonate  of  lime  or  arragonite  by  its 
action  with  acids  ;  from  a  salt  of  lead  or  any  zeolite,  by  its 
infusibility ;  from  chalcedony,  by  its  inferior  hardness  and  its 
gelatinizing  with  heated  sulphuric  acid. 

Obs.     Occurs  with  calamine.     In  the  United  States,  it  is 
found  at  ValleVs  Diggings,  at  the  Perkiomen  lead  mines  on 
the  Susquehanna,  opposite  Selimsgrove,  and  abundantly  at 
Austin's  mines,  Wythe  county,  Va. 
Uses.     Valuable  as  an  ore  of  zinc. 

Willemite  is  an  anhydrous  silicate  of  zinc,  of  a  yellowish  or  brownish 
color.  H=5 — 5-5.  Gr=4 — 4'1.  From  Limburg.  Also  said  to  occur 
at  Franklin,  N.  J. 

Mancinite  is  a  dimple  silicate  of  zinc,  of  a  brown  color,  occurring 
in  plumose  forms. 

Hopeite  is  a  rare  mineral  occurring  in  grayish-white  crystals  or  mas- 
sive, with  calamine,  and  supposed  to  be  a  phosphate  of  zinc. 

Franklinite,  an  ore  of  iron,  manganese  and  zinc,  is  described  under 
Iron,  on  page  221. 

Aurichalcite  is  a  hydrous  carbonate  of  zinc  and  copper,  occurring  in 
drusy  incrustations  of  acicular  crystals,  having  a  verdigris  green  color. 
From  Siberia. 

GENERAL  REMARKS  ON  ZINC  AND  ITS  ORES. 

The  metal  zinc  (spelter  of  commerce)  is  supposed  to  have  been  un- 
known in  the  metallic  state  to  the  Greeks  and  Romans.  It  has  been 
long  worked  in  China,  and  was  formerly  imported  in  large  quantities  by 
the  East  India  Company.  The  ores  from  which  it  is  obtained  are  the 
carbonate  and  silicate  of  zinc,  (calamine  and  electric  calamine,)  and  to 
some  extent  the  sulphuret,  (blende,)  and  .the  oxyd.  Blende,  the  black 
jack  of  English  miners,  was  considered  useless  until  the  year  1738,  when 
a  mode  of  reducing  it  was  introduced. 

The  principal  mining  regions  of  zinc  in  the  world  are  in  Upper  Silesia 
at  Tarnowitz  and  elsewhere  ;  in  Poland  ;  in  Carinthia  at  Raibel  and  Blei- 
berg  ;  in  Netherlands  at  Limberg  ;  at  Altenberg,  near  Aix-la-Chapelle 
hi  the  Prussian  province  of  the  Lower  Rhine  ;  in  England,  in  Derby- 
shire, Alstonmoor,  Mendip  Hills,  etc. ;  in  the  Altai  in  Russia  ;  besides 
others  in  China,  of  which  little  is  known.  In  the  United  States,  the 
calamine  and  electric  calamine  occur  with  the  lead  of  the  west  in  large 

How  is  electric  calamine  distinguished  from  calc  spar  and  chalcedony  1 
From  what  ores  is  the  metal  zinc  obtained  ?  What  is  zinc  called  in 
commerce  ?  When  was  blende  first  used  in  England  ?  Where  are 
zinc  mines  in  the  United  States  ? 


TIXC    ORES. 


255 


qaantities,  and  till  a  recent  period  were  considered  worthless  and  thrown 
aside  under  the  name  of"  dry  bone."  In  Tennessee,  Claiborne  county, 
there  are  workable  mines  of  the  same  ores.  The  red  oxyd  of  zinc  of 
Franklin,  New  Jersey,  contains  75  per  cent,  of  pure  zinc,  and  the  ore 
is  a  valuable  one,  although  some  difficulties  attend  its  separation  from 
the  associated  material.  Blende  is  sufficiently  abundant  to  be  worked 
at  the  Wurtzboro  lead  mine,  Sullivan  county,  N.  Y. ;  at  Eaton  and 
Warren  in  New  Hampshire  ;  at  Lubec  in  Maine  ;  and  at  Austin's  mine, 
Wythe  county,  Virginia. 

The  calamine  and  electric  calamine  are  prepared  for  reduction  by 
breaking  the  ore  into  small  fragments, separating  the  impurities  as  far  as 
possible,  and  then  calcining  in  a  reverberatory  furnace.  This  furnace 
differs  liule  from  that  figured  on  a  following  page  under  SUver*  except 
that  the  sole  is  flat.  The  ore  is  frequently  stirred,  and  after  five  or  six 
hours  it  is  taken  out ;  by  this  process,  water  and  carbonic  acid  are  ex- 
pelled. The  prepared  ore  is  then  mixed  with  about  one-seventh  by 
weight  of  charcoal,  and  in  the  English  process,  is  reduced  in  large 
crucibles. 

Figure  1,  represents  a  vertical  section  of  the  furnace,  and  figure  2, 
1 


half  of  a  horizontal  section  across  the  line  1, 2.     The  oven  has  an  arched 
or  cupola  top,  (*,)  and  contains  6  or  8  crucibles  or  pots,  (A,  A,  A,  A,) 

2 


placed  upon  the  sole  of  the  earth,  (i,  i, «, «.)     The  crucibles  bar*  a  hole 


How  is  ealamiae  reduce  I ! 


256  METALS. 

at  bottom,  to  which  a  sheet  iron  tube  (&)  is  adapted,  which  tube  extends 
down  to  small  vessels  of  water,  or  condensers,  (Z,  I)  ;  and  the  sole  of  the 
hearth  is  perforated  accordingly  below  each  crucible.  If  one  of  the  tubes 
becomes  clogged  with  metal,  it  is  cleared  by  a  hot  iron  bar.  In  charg- 
ing, the  hole  in  the  bottom  of  the  crucible  is  stopped  by  a  wooden  plug, 
which  afterwards  becomes  reduced  to  charcoal  by  the  heat.  The  pots 
are  charged  and  cleared  out  through  holes  (d,  d,  d,  d)  in  the  cupola  (a.) 
The  covers  (of  fire-tile,  m)  are  placed  on  whenever  a  blue  flame  begins 
to  appear,  as  this  indicates  the  vaporization  of  the  zinc. 

The  fire  is  made  on  the  grate  ef  through  the  door/;  g  is  the  ash-pit 
below  ;  ?»,  m,  m,  m,  in  figure  2,  show  the  position  of  the  pots  as  seen  in 
a  bird's-eye  view.  The  smoke  escapes  from  the  oven  by  the  apertures 
d,  (fig.  1,)  into  a  conical  chimney,  (&,)  by  which  a  strong  draught  is 
kept  up.  In  this  chimney  there  are  as  many  doors  (c,  cf  cf  c)  as  there 
are  pots;  and  in  the  cupola  there  are  the  same  number  of  openings  for 
inserting  or  removing  the  pots,  which  are  afterwards  closed  up  by 
brickwork ;  the  pots  are  many  times  refilled  without  removal.  The 
refuse  after  an  operation,  is  shaken  out  through  the  hole  in  the  bottom 
of  each  pot,  after  the  tube  k  is  removed. 

The  zinc  as  it  is  reduced,  rises  in  vapor  and  passes  down  the  tubes  into 
the  condensers,  where  it  collects  in  drops  or  powder  with  sorae  oxydl  j 
the  metal  is  afterwards  melted  and  cast  into  bars  ;  and  the  oxyd  which 
is  skimmed  off  is  returned  to  the  crucibles.  A  charge  occupies  about 
three  days,  and  the  ore  affords  from  25  to  40  per  cent,  of  zinc. 

In  Liege,  where  the  ore  from  Altenberg  is  reduced,  the  ore  is  heated 
in  horizontal  earthen  tubes.,  3  feet  long  and  4  to  6  inches  in  diameter, 
set  thickly  across  a  furnace,  and  around  which  the  heat  circulates. 
From  the  description  given,  it  is  obvious  how  the  process  might  be 
Taried,  and  larger  combinations  of  pots  or  tubes  arranged. 

The  blende  is  roasted  in  a  reverberatory  furnace,  8  or  10  feet  square, 
the  ore  being  placed  in  the  furnace  several  inches  deep,  and  kept  con- 
stantly stirred  for  10  or  12  hours.  The  roasted  ore  is  then  reduced  ia 
crucibles  in  the  same  manner  as  above  explained.  In  England,  the 
roasted  blende  is  mixed  with  as  much  calcined  calamine  and  twice  the 
quantity  of  charcoal. 

The  annual  production  of  zinc  in  different  countries  is  as  follows : 

Great  Britain,        ....  S.5,000  cwt. 

Upper  Silesia  and  Poland,      uf,»    .-,  50,000  " 

Aix-la-Chapelle,   ....  35,000  " 

Belgium,       .         .  .,,  .^,  .'•„..        .  18,000  " 

Carinthia,     .      Vn    V#V  .        .  3,400  " 

Brass  is  made  directly  from  the  ore  by  heating  copper  with  calcined! 
ealamine  and  charcoal.  At  Holy-well,  England,  40  pounds  of  copper 
and  60  of  calamine  yield  about  60  pounds  of  brass.  It  is  also  made 
from  copper  and  roasted  blende,  but  the  product  is  less  pure.  Dr.  Jack- 
son states  that  he  has  obtained  brass  of  an  inferior  quality  by  heating 
together  in  a  crucible  copper  pyrites  and  blende  after  roaming-  them. 
Brass  is  commonly  made  in  this  country  by  melting  together  the  metals 
zinc  and  copper. 

How  is  blende  reduced  I     How  is  brass  made  I 


BISMUTH.  257 

The  proportions  of  zinc  in  its  alloys  with  copper  are  given  in  the  re- 
marks on  copper.  Zinc  is  a  brittle  metal,  but  admits  of  being  rolled  into 
sheets  when  heated  to  about  212°  F.  In  sheets  it  is  extensively  used  for 
roofing  and  other  purposes,  it  being  of  more  difficult  corrosion,  much 
harder,  and  also  very  much  lighter  than  lead.  Its  combustibility  13  a 
strong  objection  to  k  as  a  roofing  material. 

The  Biddery  ware  of  the  East  Indies  is  made  from  an  alloy  of  copper 
I6oz.,  lead  4oz.,  and  tin  2oz.,  which  is  melted  together  and  then  mixed 
with  I6oz.  of  spelter  to  every  3oz.  of  alloy. 

The  white  oxyd  of  zinc  is  much  used  for  white  paint,  in  place  of 
white  lead. 

An  impure  oxyd  of  zinc  called  cadtnia,  often  collects  in  large  quan- 
tities in  the  flues  of  iron  and  other  furnaces,  derired  from  ores  of  zinc 
mixed  with  the  ores  undergoing  reduction.  A  mass  weighing  600 
pounds  was  taken  from  a  furnace  at  Bennington,  Vt.  It  has  been  ob- 
served in  the  Salisbury  iron  furnace,  and  at  Ancrarn  in  New  Jersey, 
where  it  was  formerly  called  ancramite. 

10.       CADMIUM, 

There  is  but  a  single  known  ore  of  this  rare  metal.  It  is 
a  sulphuret,  and  is  called  greenockite.  It  occurs  in  hexago- 
nal prisms,  with  pyramidal  terminations,  of  a  yellow  color, 
high  luster,  and  nearly  transparent.  H  =  3 — 3'5.  Gr  = 
4*8 — 4-9.  From  Bishopton,  Scotland. 

Cadmium  is  often  associated  in  small  quantities  with  zinc 
blende  and  calamine.  In  a  black  fibrous  blende  from  Przi- 
brarn,  Lowe  found  1*5  to  1*8  per  cent. 

1L    BISMUTH. 

Bismuth  occurs  native,  and  also  in  combination  with  sul- 
phur, tellurium,  oxygen,  carbonic  acid  and  silica.  The  ores 
fuse  easily  before  the  blowpipe,  and  an  oxyd  is  produced 
which  stains  the  charcoal  brownish  or  yellow,  without  rising 
in  fumes.*  Specific  gavity  of  the  ores  between  4'3  and 
9-5. 

, 

What  is  said  of  the  metal  zinc  1  What  ore  is  there  of  cadmium  1 
With  what  ores  is  cadmium  usually  associated  ?  What  is  said  of  bis- 
muth and  its  ores  ? 

*  Tellurium  produces  a  similar  stain  on  charcoal,  but  on  directing  the 
jnner  flame  on  the  coating,  it  colors  the  flai  je  strongly  green,  while 
with  bismuth  no  color  is  obtained.  Antimony  gives  white  fumes,  pro- 
ducing a  white  coating  on  charcoal,  and  the  flame  directed  on  it  is 
colored  greenish-blue. 

22* 


METALS, 


NATIVE    BISMUTH. 

Monometric.  Cleavage  octahedral,  perfect.  In  cubes  or 
octahedrons  generally  massive,  with  distinct  cleavage  ;  some- 
times granular. 

Color  and  streak  silver  white,  with  a  slight  tinge  of  red. 
Subject  to  tarnish.  Brittle  when  cold,  but  somewhat  mal- 
leable when  heated.  11=2 — 2-5.  Gr=&-7 — 9'8.  Fuses 
at  a  temperature  of  476^  F. 

Composition :  pure  bismuth,  with  sometimes  a  trace  of 
arsenic.  Evaporates  before  the  blowpipe,  and  leaves  a 
yellow  coating  on  charcoal. 

Obs.  Bismuth  is  abundant  writh  the  ores  of  silver  and  co- 
balt of  Saxony  and  Bohemia,  and  occurs  also  in  Cornwall 
and  Cumberland,  England.  At  Schneeberg,  it  forms  arbo- 
rescent delineations  in  brown  jasper. 

In  the  United  States,  it  has  been  found  at  Lane's  mine, 
Monroe,  where  it  occurs  with  tungsten,  galena,  and  pyrites, 
but  is  not  abundant ;  also  at  Brewer's  mine,  in  Chesterfield 
district,  South  Carolina. 

There  are  other  ores  of  bismuth,  but  none  of  them  are  common. 

Sulphuret  of  bismuth.  Massive  and  in  acicular  crystals,  of  a  lead- 
gray  color.  H=2 — 25.  Gr=6'55.  Contains  bismuth  81,  sulphur 
18'7.  Fuses  in  the  flame  of  a  candle.  From  Cumberland,  Cornwall, 
Johanngeorgenstadt,  and  Sweden. 

Acicular  bismuth.  A  sulphuret  of  bismuth,  lead,  and  copper,  con- 
taining a  trace  of  gold.  In  acicular  crystals  of  a  dark  lead-gray  color, 
with  a  pale  copper-red  tarnish.  Gr=6'l.  Fuses  easily,  emitting  fumes 
of  sulphur.  From  Siberia.  A  cupreous  bismuth,  of  a  pale  lead-gray 
color,  contains  34' 7  per  cent,  of  copper. 

Tetradymite.  Consists  of  tellurium  and  bismuth.  It  has  a  foliated 
structure,  a  pale  steel-gray  color,  and  soils  like  molybdenite.  Gr=7'5. 
From  Sc.hemnitz,  and  Retzbanya,  and  also  from  Brazil. 

Bismutite.  In  acicular  crystals  and  massive.  Color  greenish  or  yel- 
lowish. H=4 — 4-5.  Gr=6-8 — 6'9.  It  is  a  carbonate  of  bismuth. 
From  Cornwall  and  European  mines.  Bismuth  ocher  is  another  car- 
bonate, occurring  massive  and  earthy  ;  color  greenish,  yellowish,  or 
grayish- white.  From  Saxony,  Bohemia,  and  Siberia. 

Bismuth  blende  is  a  silicate  of  bismuth.  Color  dark  hair-brown,  or 
yellow.  H=3'5 — 4'5.  Gr=5'9 — 6'0.  In  dodecahedrons  and  mas- 
eive.  From  Saxony. 


What  are  the  color  and  physical  characters  generally  of  native  bis- 
muth 1  What  is  its  temperature  of  fusion  I  With  what  ores  is  it  usually 
associated. 


BISMUTH. 


GENERAL  REMARKS  ON  BISMUTH  AND  ITS  ORES. 

The  first  notice  of  the  metal  bismuth  is  in  the  writings  of  Agricola, 
in  1529.  It  is  known  in  the  arts  under  the  name  of  tin  glass,  from  the 
French  name  etain  de  glace.  It  is  obtained  for  the  arts  from  the  native 
bismuth  alone,  and  much  the  greater  part  of  the  metal  comes  from 
Schneeberg  in  Saxony.  The  American  mine  at  Monroe,  Conn.,  has 
been  but  little  explored,  and  has  afforded  only  a  few  small  specimens. 
The  metal  is  obtained  by  heating  the  powdered  ore  in  a  furnace,  when 
the  bismuth  melts,  and  separating  from  the  gangue,  is  drawn  off  into 
cast  iron  moulds. 

Bismuth  is  employed  in  the  manufacture  of  the  best  type  metal,  to 
give  a  sharp,  clear  face  to  the  letter.  Equal  parts  of  tin,  bismuth,  and 
mercury  form  the  mosaic  gold  used  for  various  ornamental  purposes. 
Plumber's  solder,  used  for  soldering  pewter  wares  and  other  purposes, 
consists  of  1  part  of  bismuth,  5  of  lead,  and  3  of  tin.  Bismuth  is  one  of 
the  constituents  of  fusible  metal,  of  which  spoons  are  made,  as  toys,  that 
will  melt  on  putting  them  into  a  cup  of  hot  tea  ;  this  fusible  alloy  con- 
sists of  8  parts  of  bismuth,  5  of  lead,  and  3  of  tin  ;  or  better  of  10^  parts 
of  bismuth,  5  parts  of  lead,  and  3  of  tin.  It  may  be  rendered  more 
fusible  still  by  adding  mercury.  An  alloy  of  tin  and  bismuth  in  equal 
parts  melts  at  280°  F.  But  with  less  bismuth  tin  is  increased  in 
hardness. 

The  magestens  of  bismuth,  a  white  hydrated  oxyd  precipitated  by 
adding  water  to  a  solution  of  the  nitrate,  is  used  as  a  cosmetic.  It  con- 
tains a  little  nitric  acid.  Pearl  powder  is  a  similar  preparation  made  in 
the  same  way  from  a  nitrate  containing  some  chlorid  of  bismuth.  These 
powders  blacken  when  exposed  to  an  offensive  atmosphere. 

12.     LEAD. 

Lead  occurs  rarely  native  ;  generally  in  combination  with 
sulphur  ;  also  with  arsenic,  tellurium,  selenium,  and  various 
acids. 

The  ores  of  lead  vary  in  specific  gravity  from  5'5 — 8*2. 
They  are  soft,  the  hardness  of  the  species  with  metallic  lus- 
ter not  exceeding  3,  and  others  not  over  4.  They  are  easily 
fusible  before  the  blowpipe,  (excepting  plumbo-resinite) ;  and 
with  carbonate  of  soda  on  charcoal,  (and  often  alone,)  mal- 
leable lead  may  be  obtained.  The  lead  often  passes  off  in 
yellow  fumes,  when  the  mineral  is  heated  in  the  outer  flame, 
or  it  covers  the  charcoal  with  a  yellow  coating. 

Where  have  we  the  first  notice  of  the  metal  bismuth  ?  From  what 
source  is  it  obtained  for  the  arts  ?  What  is  it  often  called  in  the  arts? 
How  is  the  metal  obtained  ?  For  what  is  bismuth  used  ]  How  does 
lead  occur  in  nature  I  What  is  said  of  the  tests  ? 


260  METALS. 


NATIVE    LEAD. 

A  rare  mineral,  occurring  in  thin  laminae  or  globules 
Gi=ll'35.  Said  to  have  been  seen  in  the  lava  of  Madeira  ; 
at  Alston  in  Cumberland  with  galena ;  in  the  county  of 
Kerry,  Ireland ;  and  in  an  argillaceous  rock  at  Carthagena. 

GALENA. — Sulphur et  of  Lead. 

Monometric.     Cleavage  cubic,  eminent.     Occurs  under 
the  form  of  the  cube  and  its  secondaries. 
TF 


Cleavage  cubic,  perfect,  and  very  easily  obtained.  Also 
coarse  or  fine  granular  ;  rarely  fibrous. 

Color  and  streak  lead  gray.  Luster  shining  metallic. 
Fragile.  H  =  2-5.  Gr=  7.5—7-7. 

Composition :  when  pure,  lead  86*55,  sulphur  13'45. 
Often  contains  some  sulphuret  of  silver,  and  is  then  called 
argentiferous  galena,  and  at  times  sulphuret  of  zinc  is  pres- 
ent. Before  the  blowpipe  on  charcoal,  it  decrepitates  un- 
less heated  with  caution,  and  fuses,  giving  off  sulphur,  and 
finally  yields  a  globule  of  lead. 

Dif.  Galena  resembles  some  silver  and  copper  ores  in 
color,  but  its  cubical  cleavage,  or  granular  structure  when 
massive,  will  usually  distinguish  it.  Its  sulphur  fumes  ob- 
tained before  the  blowpipe  prove  it  to  be  a  sulphuret ;  and 
the  lead  reaction  before  the  blowpipe  show  it  to  be  a  lead 
ore. 

Obs.  Galena  occurs  in  granite,  limestone,  argillaceous 
and  sandstone  rocks,  and  is  often  associated  with  ores  of 
zinc,  silver  and  copper.  Quartz  heavy  spar,  or  carbonate 
of  lime,  is  generally  the  gangue  of  the  ore ;  also  at  times 
fluor  spar.  The  rich  lead  mines  of  Derbyshire  and  the 
northern  districts  of  England,  occur  in  mountain  limestone  ; 
and  the  same  rock  contains  the  valuable  deposits  of  Bleiberg 

Where  has  native  lead  been  found  1  What  is  the  structure  of  galena  1 
its  physical  characters  ?  its  composition  and  blowpipe  characters  ? 
How  is  it  distinguished  from  silver  and  copper  ores  1  Where  does,  it 
occur  ] 


LEAD    OKES.  261 

and  the  neighboring  deposits  of  Carinthia.  At  Freiberg  in 
Saxony,  it  occupies  veins  in  gneiss ;  in  the  Upper  Hartz,  and 
at  Przibram  in  Bohemia,  it  traverses  clay  slate ;  at  Sahla, 
Sweden,  it  occurs  in  crystalline  limestone  ;  the  ore  of  Lead- 
hills,  England,  is  in  graywacke.  There  are  other  valuable 
beds  of  galena,  in  France  at  Poullaouen  and  Huelgoet,  Brit- 
tany, and  at  Villefort,  department  of  Lozere  ;  in  Spain  in  the 
granite  hills  of  Lihares,  in  Catalonia,  Grenada  and  else- 
where ;  in  Savoy ;  in  Netherlands  at  Vedrin,  not  far  from 
Namur ;  in  Bohemia,  southwest  of  Prague  ;  in  Joachimstahl, 
where  the  ore  is  worked  principally  for  its  silver  ;  in  Siberia 
in  the  Daouria  mountains  in  limestone,  argentiferous  and 
worked  for  the  silver. 

The  deposits  of  this  ore  in  the  United  States  are  remark- 
able for  their  extent.  They  abound  in  what  has  been  called 
"  cliff  limestone,"  in  the  states  of  Missouri,  Illinois,  Iowa,  and 
Wisconsin  ;  argillaceous  iron,  iron  pyrites,  calamine,  ("  dry 
bone"  of  the  miners,)  blende,  ("  black  jack,")  carbonate 
and  sulphate  of  lead,  are  the  most  common  associated  min- 
erals, together  often  with  ores  of  copper  and  cobalt.  In 
1720,  the  lead  mines  of  Missouri  were  discovered  by  Francis 
Renault  and  M.  La  Motte ;  and  the  La  Motte  mine  is  still 
known  by  this  name.  Afterwards,  the  country  passed  into 
the  hands  of  the  Spaniards,  and  during  that  period  a  valu- 
able mine  was  opened  by  Mr.  Burton,  since  called  Mine  d 
Burton.  The  mines  of  Missouri  are  contained  in  the  coun- 
ties of  Washington,  Jefferson,  and  Madison. 

The  lead  region  of  Wisconsin,  according  to  Mr.  D.  D. 
Owen,  comprises  62  townships  in  Wisconsin,  8  in  Iowa,  and 
10  in  Illinois,  being  87  miles  from  east  to  west,  and  54  miles 
from  north  to  south.  The  ore,  as  in  Missouri,  is  inexhaust- 
ible, and  throughout  the  region,  there  is  scarcely  a  square 
mile  in  which  traces  of  lead  may  not  be  found.  The  prin- 
cipal indications  in  the  eyes  of  miners,  as  stated  by  Mr. 
Owen,  are  the  following  :  fragments  of  calc  spar  in  the  soil, 
unless  very  abundant,  which  then  indicate  that  the  vein  is 
wholly  calcareous  or  nearly  so  ;  the  red  color  of  the  soil  on 
the  surface,  arising  from  the  ferruginous  clay  in  which  the 
lead  is  often  imbedded ;  fragments  of  lead  ("  gravel  mineral,") 
along  with  the  crumbling  magnesian  limestone,  and  dendritic 
specks  distributed  over  the  rock  ;  also,  a  depression  of  the 

What  ia  said  of  the  extent  of  the  United  States  mines? 


262  METALS. 

country,  or  an  elevation,  in  a  straight  line  ;  or  "  sinkholes  ;" 
or  a  peculiarity  of  vegetation  in  a  linear  direction.  The 
"  diggings"  seldom  exceed  25  or  30  feet  in  depth  ;  for  the 
galena  is  so  abundant  that  a  new  spot  is  chosen  rather  than 
the  expense  of  deeper  mining.  From  a  single  spot,  not  ex- 
ceeding 50  yards  square,  3,000,000  Ibs.  of  ore  have  been 
raised  ;  and  at  the  diggings  in  the  west  branch  of  the  Pecca- 
tonica,  not  over  12  feet  deep,  two  men  can  raise  2000  Ibs. 
per  day  ;  in  one  of  the  townships,  two  men  raised  16,000  Ibs. 
in  a  day ;  500  Ibs.  is  the  usual  day's  labor  from  the  mines 
of  average  productiveness. 

Galena  also  occurs  in  the  region  of  Chocolate  river  and 
elsewhere,  Lake  Superior  copper  region  ;  at  Cave-in-Rock 
in  Illinois,  along  with  fluor  ;  in  New  York  at  Rossie,  St. 
Lawrence  county,  in  gneiss,  in  a  vein  3  to  4  feet  wide ;  near 
Wurtzboro'  in  Sullivan  county,  a  large  vein  in  millstone  grit; 
at  Ancram,  Columbia  county  ;  Martinsburg,  Lewis  county, 
N.  Y.,  and  Lowville,  are  other  localities.  All  these  mines 
have  been  worked,  but  they  are  now  abandoned.  Dr.  Beck 
says  of  the  Sullivan  county  and  St.  Lawrence  mines,  "  in 
the  latter  the  ore  is  in  small  veins  with  good  associates,  and 
Is  easily  reduced ;  but  the  situation  of  the  mines  is  bad. 
In  the  former,  the  ore  is  in  large  veins  with  bad  associates, 
(zinc  blende,)  and  is  more  difficult  of  separation  and  reduc- 
tion ;  but  the  mines  are  admirably  situated,  whether  we  re- 
gard the  removal  of  the  ore  or  the  facility  of  transporting 
produce  to  them." 

In  Maine,  veins  of  considerable  extent  occur  at  Lubec ; 
also  ofless  interest  at  Blue  Hill  Bay,  Birmingham  and  Par- 
sonsfield.  In  New  Hampshire,  galena  occurs  at  Eaton,  Bath, 
Tamworth  and  Haverhill.  In  Vermont,  at  Thetford  ;  in 
Massachusetts,  at  Southampton,  Leverett,  and  Sterling,  but 
without  promise  to  the  miner.  In  Virginia,  in  Wythe  coun- 
ty, Louisa  county,  and  elsewhere.  In  North  Carolina,  at 
King's  mine,  Davidson  county,  where  the  lead  appears  to  be 
abundant.  In  Tennessee,  at  Brown's  creek,  and  at  Hays- 
boro',  near  Nashville,  An  argentiferous  variety  occurs 
sparingly  at  Monroe,  Conn.,  which  afforded  Prof.  Silliman 
by  cupellation  3  per  cent,  of  silver. 

Uses.  The  lead  of  com  H3rce  is  obtained  from  this  ore. 
It  is  often  worked  also  for  the  silver  it  contains.  It  is  also 
employed  in  glazing  common  stone  ware  :  for  this  purpose 
it  is  ground  up  to  an  impalpable  powder  and  mixed  in  water 


LEAD    ORES.  263 

with  clay  ;   into  this  liq  li  I  the  earthen  vessel  is  dipped  and 
then  bdked. 

Cuproplmnbite  is  a  galena  containing  24' 5  per  cent,  of  sulphuret  of 
copper.  From  Chili. 

ARSEXURETS,   SELEJTIDS,    AND   TELLUKIDS   OF   LEAD. 

These  various  ores  of  lead  are  distinguished  by  the  fumes  before  the 
blowpipe,  and  by  yielding  ultimately  a  globule  of  lead. 

Cobiltic  lead  ore  is  an  ars^niuret  of  lead,  containing  a  trace  of  cobalt. 
From  \\\f  Hartz.  Gives  an  alliaceous  odor  (from  the  arsenic)  before 
the  blowpipe.  Gi=*844. 

Dufrenoysile  is  an  arseniuret  and  sulphuret  of  lead  ;  in  dodecahe- 
drons of  a  dark  steel-gray  color.  Gr=5~55.  .From  the  Dolomite  of  St. 
Gothard. 

Clau9tfialite,  or  selenid  of  lead,  has  a  lead-gray  color,  and  granular 
fracture.  Gr=7'19.  Gives  a  horse-radish  odor  (that  of  selenium)  be- 
fore the  blowpipe.  From  the  Hartz.  There  are  three  selenids  of  lead 
and  copper  which  give  the  reaction  of  all  the  different  constituents  be- 
fore the  blowpipe.  The  sp.  gr.  of  one  is  5'6  ;  of  the  second  7'0 ;  the 
third  74.  From  the  Hartz.  There  is  also  a  selenid  of  lead  and  mer- 
cury occurring  in  foliated  grains  or  masses,  of  a  lead-gray  to  bluish  and 
iron-black  color. 

Tdlurid  of  lead.  This  is  a  tin-white  cleavable  mineral.  Gr=8'l6. 
From  the  Altai  mountains. 

Foliated  tellurium  is  a  less  rare  species,  remarkable  for  being  foli- 
ated like  graphite.  Color  and  streak  blackish  lead-gray.  H=l — 1-5. 
Gr=7  085.  It  contains  tellurium  32-2,  lead  54'0,  gold  90,  with  often 
silver,  copper,  and  some  sulphur.  From  Transylvania. 

MINIUM. — Oxyd  of  Lead. 

Pulverulent.  Color  bright  red,  mixed  with  yellow.  Gr= 
4'6.  It  is  a  sesquioxyd  of  lead.  Affords  globules  of  lead 
in  the  reduction  flame  of  the  blowpipe. 

Obs.  Occurs  at  various  mines,  usually  associated  with 
galena,  and  is  found  abundantly  at  Austin's  mines,  Wythe 
county,  Virginia,  with  white  lead  ore. 

Uses.  Minium  is  the  red  lead  of  commerce :  but  for  the 
arts  it  is  artificially  prepared.  Lead  is  calcined  in  a  rever- 
beratory  furnace,  and  a  yellow  oxyd  (massicot)  is  thus 
formed :  the  massicot  is  afterwards  heated  in  the  same  fur- 
nace in  iron  trays,  at  a  low  temperature,  by  which  the  lead 
absorbs  more  oxygen  and  becomes  red  lead.  A  much  better 
material  is  obtained  by  the  slow  calcination  of  white  lead. 

Plumbic  ocher  is  another  similar  ore,  of  a  yellow  color  ;  it  is  a  pro- 
toxyd  of  lead.  Occurs  in  Wythe  county,  Va. 

What  is  minium]     What  are  its  characters  ? 


264  METALS. 

ANGLESITE. — Sulphate  of  Lead. 

Primary  form  a  right  rhombic  prism,  with  imperfect  lat. 
eral  cleavage.  M  :  M— 103°  49 .  Often  in  slender  im- 
planted crystals.  Also  massive  ;  lamellar  or  granular. 

Color  white  or  slightly  gray  or  green.  Luster  adaman- 
tine ;  sometimes  a  little  resinous  or  vitreous.  Transparent 
to  nearly  opaque.  Brittle.  H=2'75— 3.  Gr=6'25— 6-3. 

Composition :  a  sulphate  of  lead,  containing  about  73  per 
cent,  of  oxyd  of  lead.  Fuses  before  the  blowpipe  to  a  slag, 
and  yields  lead  with  carbonate  of  soda. 

Dif.  Resembles  somewhat  some  of  the  zeolite  minerals, 
and  also  arragonite  and  some  other  earthy  species  ;  but  this 
and  the  other  ores  of  lead  are  at  once  distinguished  by  spe- 
cific gravity,  and  also  by  their  yielding  lead  in  blowpipe 
trials.  Differs  from  the  carbonate  of  lead  in  not  dissolving 
with  effervescence  in  nitric  acid. 

Obs.  Usually  associated  with  galena,  and  results  from 
its  decomposition.  Occurs  in  fine  crystals  at  Leadhills  and 
Wanlockhead,  Great  Britain,  and  also  at  other  foreign  lead 
mines.  In  the  United  States,  it  is  found  at  the  lead  mines 
of  Missouri  and  Wisconsin.  It  has  been  met  with  sparingly 
at  the  Rossie  lead  mine  ;  at  the  Walton  gold  mine,  Louisa 
county,  Va.  ;  at  Southampton,  Mass. 

Cupreous  anglesite.  A  hydrous  azure-blue  sulphate  of  lead  and 
copper.  It  is  remarkable  for  a  very  perfect  cleavage  in  two  directions, 
inclined  to  one  another,  95°  45'.  Gr=5'3 — 55.  From  Leadhills  and 
Roughten  Gill,  England.  Very  rare. 

WHITE  LEAD  ORE. —  Carbonate  of  Lead. 

Trimetric.     In  modified  right  rhombic  prisms.     M  :  M= 
1  2  3 


117°  13'.     M  :  e=121°  24  ;   a  :  0  =  140°  15'.     Often  i 


in 


What  is  the  appearance  of  anglesite  ?  its  composition  ?  How  is  it 
distinguished  from  arragonite  and  the  zeolites  ?  What  is  the  crystal- 
lization of  white  lead  ore  ? 


LEAD    ORES.  265 

compound  crystals,  either  six-sided  prisms  like  arragonite,  or 
wheel-shaped  groups  of  4  or  6  rays  (fig.  3.)  Also  massive  ; 
rarely  fibrous. 

Color  white,  grayish,  light  or  dark.  Luster  adamantine. 
Brittle.  H=3— 3-5.  Gr  =  6-46— 6-48. 

Composition :  oxyd  of  lead  83*46,  carbonic  acid  16*54. 
Decrepitates  before  the  blowpipe,  fuses,  and  with  care  af- 
fords a  globule  of  lead.  Effervesces  in  dilute  nitric  acid. 

Dif.  Like  anglesite,  distinguished  from  most  of  the 
species  it  resembles  by  its  specific  gravity  and  yielding  lead 
when  heated.  From  anglesite  it  differs  in  giving  lead  alone 
before  the  blowpipe,  as  well  as  by  its  solution  and  efferves- 
cence with  nitric  acid. 

Obs.  Associated  usually  with  galena.  Leadhills,  Wan- 
lockhead,  and  Cornwall,  have  afforded  splendid  crystalli- 
zations ;  also  other  lead  mines  on  the  continent  of  Europe. 

In  the  United  States,  very  handsome  specimens  are  ob- 
tained at  Austin's  mines,  Wythe  county,  Virginia,  and  at 
King's  mine  in  Davidson's  county,  North  Carolina.  At  the 
latter  place  it  constitutes  a  wide  vein,  and  has  been  worked 
for  lead.  It  is  associated  with  native  silver  and  phosphate 
of  lead.  The  Perkiomen  lead  mine,  Pa.,  has  afforded  good 
crystals.  It  occurs  also  at  "  Vallee's  Diggings,"  Jefferson 
county,  Missouri ;  at  Brigham's  mine  near  the  Blue  Mounds, 
Wisconsin  ;  at  "  Deep  Diggings"  in  crystals  ;  and  at  other 
places  in  the  West,  both  massive  and  in  fine  crystallizations. 
Rossie,  N.  Y.,  and  Southampton,  Mass.,  have  afforded  this 
ore. 

Uses.  When  abundant,  this  ore  is  wrought  for  lead.  Large 
quantities  occur  about  the  mines  of  the  Mississippi  valley. 
It  was  formerly  buried  up  in  the  rubbish  as  useless,  but  it 
has  since  been  collected  and  smelted.  It  is  an  exceedingly 
rich  ore,  affording  in  the  pure  state  75  per  cent  of  lead. 

Carbonate  of  lead  is  the  "  white  lead"  of  commerce,  sc 
extensively  used  as  a  paint.  The  material  for  this  purpose 
is,  however,  artificially  made.  In  most  manufacturing  es- 
tablishments, sheets  of  lead  are  suspended  over  a  liquid  made 
of  vinegar  and  wine  lees,  and  a  gentle  heat  is  applied  either 


What  are  the  color  and  luster  of  white  lead  ore?  its  composition  and 
blowpipe  reaction  ?  How  is  it  distinguished  from  anglesite  ?  How 
from  minerals  not  lead  ores  ?  What  use  is  made  of  white  lead  ?  How 
is  white  lead  manufactured  ? 

23 


266  METALS. 

by  stoves  or  from  fermenting  bark  ;  the  re.sult  is  that  the  lead 
becomes  carbonated  from  the  acid  fumes  that  rise  from  be- 
neath.*  The  carbonate  is  then  removed  by  shaking  the 
plates  smartly,  and  after  washing  and  levigation,  it  is  dried 
for  market.  According  to  another  good  process,  (Thenard's,) 
carbonic  acid,  either  from  burning  coke,  brewers'  vats,  or 
some  other  source,  is  made  to  pass  through  a  solution  of  sub- 
acetate  of  lead,  the  solution  of  subacetate  being  formed  by 
digesting  litharge  and  neutral  acetate  of  lead.  In  place  of 
this  solution,  litharge  moistened  slightly  with  vinegar,  has 
been  proposed.  In  the  processes  in  the  arts  more  litharge 
is  made  than  is  demanded  in  trade,  and  this  use  of  it  is  con- 
sidered more  economical  than  its  reduction  to  lead. 

Carbonate  of  lead,  mixed  with  sulphate  of  barytes,  forms 
what  is  called  Venice  white. 

Carbonate  and  sulphate  of  lead.  There  are  two  whitish  or  grayish 
ores  of  this  composition  called  dioxylite  and  leadhillite,  or  respectively 
sulphato- carbonate  and  sulphato-tricarbonate  of  lead.  The  former 
contains  71  per  cent,  of  carbonate  of  lead  ;  the  latter  47.  Dioxylite  has 
a  perfect  basal  cleavage.  Gr=6'2 — 6'5.  Leadhillite  cleaves  into  lami- 
nae that  are  flexible  like  gypsum.  Gr=6-8 — 7.  From  Leadhills. 

Caledonite  is  a  compound  of  the  carbonates  of  lead  and  copper  and 
sulphate  of  lead,  and  is  called  the  cupreous  sulphato-carbonate  of  lead, 
In  crystals  of  a  deep  verdigris  or  bluish  green  color.  Gr=6'4.  From 
Leadhills  and  Red  Gill  ;  also  from  the  Missouri  mines. 

PYROMORPHITE. — Phosphate  of  Lead. 

Primary  form,  a  hexagonal  prism.  Cleavage  lateral,  in 
traces.  Usual  in  clustered  hexagonal  prisms, 
forming  crusts.  Also  in  globules,  or  reniform, 
with  a  radiated  structure. 

Color  bright  green  or  brown ;  sometimes  fine 
orange-yellow,  owing  to  an  intermixture  with 
chromate  of  lead.  Streak  white  or  nearly  so.  Luster  more 
or  less  resinous.  Nearly  transparent  to  subtranslucent. 
Brittle.  H=3-5— 4.  Gr  =  6'5— 7-1. 

Composition  of  a  brown  variety  :  oxyd  of  lead  78-58,  mu- 
riatic acid  1-65,  phosphoric  acid  19-73.  Before  the  blow- 
pipe on  charcoal  fuses,  and  on  cooling,  the  globule  becomes 

Describe  pyromorphite.     Of  what  does  it  consist  ? 

*  A  subacetate  is  supposed  to  form  first,  and  then  to  be  immediately 
decomposed  by  the  rising  carbonic  acid. 


LEAD    ORES.  267 

angular.  In  the  inner  flame,  gives  off  fumes  of  lead.  With 
boracic  acid  and  iron,  gives  a  phosphuret  of  iron  and  metallic 
lead. 

Dif.  Has  some  resemblance  to  beryl  and  apatite  ;  but  is 
quite  different  in  its  action  before  the  blowpipe,  and  much 
higher  in  specific  gravity. 

Obs.  Leadhills,  Wanlockhead,  and  other  lead  mines  of 
Europe  are  foreign  localities.  In  the  United  States,  very 
handsome  crystallized  specimens  occur  at  King's  mine  in 
Davidson  county,  N.  C. :  other  localities  are  the  Perkiomen 
lead  mine  near  Philadelphia ;  the  Lubec  lead  mines,  Me.  ; 
Lenox,  N.  Y. ;  formerly,  a  mile  south  of  Sing  Sing,  N.  Y. ; 
and  the  Southampton  lead  mine,  Mass. 

The  name  pyromorphite  is  from  the  Greek  pur,  fire,  and 
morphe,  form,  alluding  to  its  crystallizing  on  cooling  from 
fusion  before  the  blowpipe. 

Mimetene.  An  arseoate  of  lead,  resembling  pyromorphite  in  crys- 
tallization, but  giving  a  garlic  odor  on  charcoal  before  the  blowpipe. 
Color  pale-yellow,  passing  into  brown.  H=2  75— 3  5.  Gr=6"41. 
From  Cornwall  and  elsewhere. 

Hedyphane.  An  arseno-phosphate  of  lead  and  lime,  containing  2 
per  cent,  of  chlorine.  It  occurs  amorphous,  of  a  whitish  color,  and  ada- 
mantine luster.  H=3'5— 4.  Gr=5-4 — 5- 5.  From  Sweden. 

CROCOISITE. — Chromate  of  Lead. 

Occurs  in  oblique  rhombic  prisms,  massive,  of  a  bright 
red  color  and  translucent.  Streak  orange-yellow.  H= 
2-5—3.  Gr=6. 

Composition  :  chromic  acid  31*85,  protoxyd  of  lead  68*15. 
Produces  a  yellow  solution  in  nitric  acid.  Blackens  and 
fuses  before  the  blowpipe,  and  forms  a  shining  slag  contain- 
ing  globules  of  lead. 

Obs.  Occurs  in  gneiss  at  Beresof  in  Siberia,  and  also  in 
Brazil.  This  is  the  chrome  yellow  of  the  painters.  It  is 
made  in  the  arts  by  adding  to  the  chromate  of  potash  in  so- 
lution, a  solution  of  acetate  or  nitrate  of  lead.  The  chro- 
mate of  potash  is  usually  procured  by  means  of  the  ore 
chromic  iron,  which  see,  (p.  223.) 

Melanochroite  is  another  chromate  of  lead,  containing  23'64  of  chro- 
mic acid,  and  having  a  dark  red  color ;  streak  brick  red.  Crystals 
usually  tabular  and  reticulately  arranged.  Gr=5-75.  From  Siberia. 

How  is  pyromorphite  distinguished  from  beryl  and  apatite  ?  What  ia 
the  color  of  chromate  of  lead  ?  its  composition  ?  What  is  it  called  in 
the  arts,  and  how  used  ] 


268  METALS. 


Vauquelinite-is  a  chromate  of  lead  and  copper,  of  a  very  dark  green 
or  pearly  black  color,  occurring  usually  in  minute  irregularly  aggregated 
crystals;  also  reniform  and  massive.  H=2'5 — 3.  Gr  =  5-5 — 5'8. 
From  Siberia  and  Brazil.  It  has  been  found  by  Dr.  Torrey  at  the  lead 
mine  near  Sing  Sing,  in  green  and  brownish-green  mainmillary  concre- 
tions, and  also  nearly  pulverulent. 

Cerasite.     A  chlorid  of  lead.     Color  white,  yellowish  or  reddish, 
nearly  opaque.     Luster  pearly.     Gr=7 — 7*1.     Contains  lead  83,  chlo 
rine   14.     From  Mendip  Hills,  Somersetshire.     Cotunnite  is  another 
chlorid  of  lead,  occurring  at  Vesuvius  in  white  acicular  crystals.     It  con- 
tains 74'5  per  cent,  of  lead. 

Corneous  lead.  A  chloro-carbonate  of  lead,  occurring  in  whitish 
adamantine  crystals.  Gr=6 — G'l.  From  Derbyshire  and  Germany. 
Also  said  to  occur  at  the  Southampton  lead  mine,  Massachusetts. 

Molybdate  of  lead.  In  dull-yellow  octahedral  crystals,  and  also 
massive.  Luster  resinous.  Contains  molybdic  acid  34'25,  protoxyd 
of  lead  64'42.  From  Bleiberg  and  elsewhere  in  Carinthia  ;  also  Hun- 
gary. It  has  been  found  in  small  quantities  at  the  Southampton  lead 
mine,  Mass.,  and  also  the  Perkiomen  lead  mine,  Penn. 

Selenale  of  lead.  A  sulphur-yellow  mineral,  occurring  in  small 
globules,  and  affording  before  the  blowpipe  on  charcoal  a  garlic  odor, 
and  finally  a  globule  of  lead. 

Vanadinite.  A  vanadate  of  lead,  occurring  in  hexagonal  prisms 
like  pyromorphite,  and  also  in  implanted  globules.  Color  yellow  to 
reddish  brown.  H=2  75.  Gr=6'6 — 73.  From  Mexico  ;  also  from 
Wanlockhead  in  Dumfriesshire. 

Tungstate  of  lead.  In  square  octahedrons  or  prisms.  Color  green, 
gray,  brown,  or  red.  Luster  resinous.  H=2'5 — 3.  Gr=7  9 — 8*1. 
Contains  52  of  tungstic  acid  and  48  of  lead. 

Plumbo-rcsinite.  In  globular  forms,  having  a  luster  somewhat  like 
gum  arabic,  and  a  yellowish  or  reddish-brown  color.  H=4 — 4-5. 
Gr=6'3 — 6'4.  Consists  of  protoxyd  of  lead  4O14,  alumina  37'00, 
water  18'8.  From  Huelgoet  in  Brittany,  and  at  a  lead  mine  in  Beaujeu ; 
also  from  the  Missouri  mines,  with  black  cobalt. 


GENERAL  REMARKS  ON  LEAD  AND  ITS  ORES. 

The  lead  of  commerce  is  derived  almost  wholly  from  the  sulphuret 
of  lead  or  galena,  the  localities  of  which  have  already  been  mentioned. 

This  ore  is  reduced  usually  by  heat  alone  in  a  reverberatory  furnace. 
The  process  consists  simply  in  burning  out  the  sulphur  after  the  ore  is 
picked,  pounded  and  washed.  The  galena  is  kept  at  a  heat  below  that 
required  for  its  fusion,  and  air  is  freely  admitted  to  aid  in  the  combus-. 
tion.  The  sulphur  is  driven  off,  leaving  the  pure  lead,  or  an  oxyd  formed 
in  the  process  which  passes  to  the  state  of  a  slag.  The  latter  is  heated 
again  with  charcoal,  which  separates  the  oxygen.  A  portion  of  quick- 
lime is  often  added  to  stiffen  the  slag.  In  England,  the  whole  ope- 
ration of  a  smelting  shift  takes  about  4£  hours,  and  four  periods  may 
be  distinguished  : — The  first  fire  for  roasting  the  ores,  which  requires 

What  is  the  source  of  the  lead  of  commerce  1  How  is  the  ore 
reduced  1 


LEAD    ORES.  269 

very  moderate  firing,  and  lasts  two  hours ;  the  second  fire  for  smelt- 
ing, requiring  a  higher  heat  with  shut  doors,  and  at  the  end  the  slags 
are  dried  up  with  lime,  and  the  furnace  is  also  allowed  to  cool  a  little  ; 
the  third  and  fourth  fires,  also  for  smelting,  requiring  a  still  higher 
temperature. 

A  furnace  for  using  the  hot  blast  with  lead  has  been  contrived.  The 
heated  blast  is  made  to  diffuse  itself  equally  through  the  whole  "  charge," 
carrying  with  it  the  flame  of  the  burning  fuel,  and  the  reduction  of  the 
ore  is  effected  with  an  economy  and  dispatch  hitherto  unknown  in  the 
processes  of  reducing  this  metal.* 

According  to  another  mode  which  has  been  practised  in  Germany 
and  France,  old  iron  (about  28  per  cent.)  is  thrown  into  the  melted  ore, 
heated  in  a  reverberatory  furnace  of  small  size  ;  the  iron  acts  by  absorb- 
ing the  sulphur,  and  the  lead  thus  reduced  flows  into  the  bottom  of  the 
basin.  There  is  here  a  gain  of  time  and  labor,  but  a  total  loss  of  the 
iron. 

The  mode  of  obtaining  the  silver  from  lead  ore,  is  mentioned  under 
Silver. 

The  principal  mines  of  lead  in  the  world  are  mentioned  under  Galena. 
The  following  is  a  statement  of  the  approximate  amount  of  lead  pro- 
duced by  the  mines  of  Europe : 


Great  Britain  and 

Ireland,  .         .  1,000,000  cwt. 
Spain,         .         .      250,000    " 
Austria,      .         .        64,000    " 
Russia  and  Poland,     10,000    " 
France,       .         .          4,700    " 


Sweden  and  Norway,      500  cwt. 
Prussia,      .         .         71,000    " 
Germany,  .         .         96,000   " 
Belgium,    .         .  4,000    " 

Piedmont  and  Switz- 
erland,  .         .  4,000    " 


The  mines  of  the  Upper  Mississippi  afforded  the  seven  years  from 
1841  to  1847,  as  shown  by  the  amount  received  at  St.  Louis, — t 

1841,  463,404  pigs,  about  70  Ibs.  1845,  757,906  pigs 

1842,  473,599    "  "  1846,  763,289     " 

1843,  581,431     «  "  1847,  767,656     " 

1844,  621,900    «  " 

The  lower  or  Missouri  mines  yielded  in  1846,  about  145,000  pigs ; 
and  in  1847,  only  125,000  pigs.  The  Missouri  lead  region  is  more  ex- 
tensive than  that  of  the  upper  mines,  but  the  latter  have  greater  facili- 
ties of  exportation.  The  metal  at  St.  Louis  brings  about  4  cents  a 
pound,  and  at  Galena  half  a  cent  less. 


What  other  method  is  mentioned  ?  What  country  affords  the  largest 
amount  of  lead  at  the  present  time,  and  how  much?  What  was  the 
yield  of  the  mines  of  the  Upper  Mississippi  in  1847  1  What  of  the  Lower 
or  Missouri  mines  ? 


*  See  Amer.  Jour.  Sci.,  xlii,  p.  169. 

t  From  a  letter  to  the  author,  by  H.  King,  of  St.  Louis.  The  amount 
received  at  St.  Louis  varies  somewhat  each  year,  with  the  state  of 
navigation. 

23* 


270  METALS. 


13.    MERCURY 

Mercury  occurs  native,  alloyed  with  silver,  and  in  coml  £ 
nation  with  sulphur,  chlorine,  or  iodine.  Its  ores  are  com- 
pletely volatile,  excepting  the  one  containing  silver. 

NATIVE    MERCURY. 

Monometric  ;  in  octahedrons.  Occurs  in  fluid  globules 
scattered  through  the  gangue.  Color  tin-white.  Gr=13-6. 
Becomes  solid  and  crystallizes  at  a  temperature  of— 39°  F. 

Mercury,  or  quicksilver  as  it  is  often  called,  (a  translation 
of  the  old  name  "  argentum  vivum,")  is  entirely  volatile  be- 
fore  the  blowpipe,  and  dissolves  readily  in  nitric  acid. 

Obs.  Native  mercury  is  a  rare  mineral,  yet  is  met  with 
at  the  different  mines  of  this  metal,  at  Almaden  in  Spain, 
Idria  in  Carniola,  (Austria,)  and  also  in  Hungaiy  and  Pern. 
It  is  usually  in  disseminated  globules,  but  is  sometimes  ac- 
cumulated in  cavities  so  as  to  be  dipped  up  in  pails. 

Uses.  Mercury  is  used  for  the  extraction  of  gold  and  sil- 
ver ores,  and  is  exported  in  large  quantities  to  South  Amer- 
ica. It  is  also  employed  for  silvering  mirrors,  for  thermome- 
ters  and  barometers,  and  for  various  purposes  connected  with 
medicine  and  the  arts. 

Native  Amalgam.  This  mineral  is  a  compound  of  mercury  and  sil- 
ver, containing  64  to  72  per  cent,  of  mercury,  and  occurring  in  silver- 
white  dodecahedrons.  H=2— 2'5.  Gr=10'5— 14.  Principally  from 
the  Palatinate  ;  also  from  Hungary  and  Sweden.  The  arqucrite  of 
Berthier  is  an  amalgam  from  Coquimbo,  containing  only  13'5  per  cent, 
of  silver. 

CINNABAR. — Sulphuret  of  Mercury. 

^  Rhombohedral.  R  :  R=71°  47'.  Cleavage  transverse, 
highly  perfect.  Crystals  often  tabular,  or  six-sided  prisms. 
Also  massive,  and  in  earthy  coatings. 

Luster  unmetallic,  adamantine  in  crystals ;  often  dull. 
Color  bright  red  to  brownish-red,  and  brownish-black. 
Streak  red.  Subtransparent  to  nearly  opaque.  H=2 — 2'5. 
Gr=6-7— 8-2.  Sectile. 

Composition  :  when  pure,  mercury  86'29,  sulphur  13-71 ; 

In  what  condition  does  mercury  occur  ?  What  is  a  characteristic  of 
its  ores  1  Describe  native  mercury  ?  Where  is  it  found  ?  For  wha{ 
is  it  used  1  What  are  the  physical  characters  of  cinnabar  ? 


ORES    OF   MERCURY.  271 

but  often  contains  impurities.  The  liver  ore,  or  hepatic  cin- 
nabar, contains  some  carbon  and  clay,  and  has  a  brown- 
ish streak  and  color.  The  pure  variety  volatilizes  entirely 
before  the  blowpipe. 

Dif.  Distinguished  from  red  oxyd  of  iron  and  chromate 
of  iron  by  evaporating  before  the  blowpipe  ;  from  realgar 
by  giving  off  on  charcoal  no  allicaceous  fumes. 

Obs.  Cinnabar  is  the  ore  from  which  the  principal  part 
of  the  mercury  of  commerce  is  obtained.  It  occurs  mostly 
in  connection  with  talcose  and  argillaceous  shale,  or  other 
stratified  deposits,  both  the  most  ancient  and  those  of  more 
recent  date.  The  mineral  is  too  volatile  to  be  expected  in 
any  abundance  in  proper  igneous  or  crystalline  rocks,  yet 
has  been  found  sparingly  in  granite.  The  principal  mines 
are  at  Idria  in  Austria,  Almaden  in  Spain,  in  the  Palatinate 
on  the  Rhine,  and  at  Huanca  Velica  in  Peru.  Mercury  oc- 
curs also  at  Arqueros  in  Chili,  at  various  places  in  Mexico, 
in  Hungary,  Sweden,  at  several  points  in  France,  and  at  Ripa, 
in  Tuscany;  also  in  China  and  Japan.  A  large  mine  has 
been  discovered  in  Upper  California.  See  Appendix,  p.  432. 

Uses.  This  ore  is  the  principal  source  of  the  mercury  of 
commerce.  It  is  also  used  as  a  pigment,  and  as  a  coloring 
ingredient  for  red  sealing  wax,  and  it  is  called  in  the  shops 
vermillion.  It  is  prepared  in  the  arts  by  first  making  the 
black  sulphuret  of  mercury,  (or  Ethiops  mineral.)  This 
may  be  done  by  heating  together  the  requisite  sulphur  and 
mercury.  This  sulphuret  is  then  heated  in  clay  vessels, 
with  certain  precautions,  and  the  vermillion — a  bisulphuret 
— is  finally  formed  and  incrusts  the  clay  vessels,  which  are 
broken  to  remove  it.  To  obtain  a  good  product  requires  at- 
tention to  many  circumstances.  Another  process  is  to  tri- 
turate together  mercury  (300  parts)  and  sulphur  (114,)  after 
a  while  adding  potash  lye  (equal  to  75  parts  of  caustic  pot- 
assa,)  and  continuing  the  trituration  until  the  black  sulphuret 
is  formed.  Then  heat  the  mixture  with  care,  to  130°  F.  in 
iron  vessels. 

The  vermillion  of  commerce  is  ofien  adulterated  with  red 
lead,  dragon's  blood  and  realgar.  Its  entire  volatility,  with- 
out odorous  fumes,  will  distinguish  the  pure  material. 

Horn  Quicksilver,  (chlorid  of  mercury.)     A  tough,  sectile  ore,  of  a 


Of  what  does  cinnabar  consist  ?     Where  are  the  principal  mines  ? 
For  what  is  it  used  ? 


272  METALS. 

light  yellowish  or  grayish  color,  and  adamantine  luster,  translucent  or 
subtranslucent,  crystallizing  in  secondaries  to  a  square  prism.  H:=l — « 
2.  Gr=6'48.  It  contains  85  per  cent,  of  mercury. 

lodic  Mercury  is  a  still  rarer  ore  from  Mexico.     Color  reddish-brown. 

Selenid  of  mercury,  a  dark  steel-gray  ore,  which  is  wholly  evapo- 
rated before  the  blowpipe.  Occurs  in  Mexico  near  San  Onofre. 

GENERAL  REMARKS  ON  THE  ORES  OF  MERCURY. 

The  mines  of  Idria  were  discovered  in  1497.  The  mining  is  carried 
on  in  galleries,  as  the  rock  is  too  fragile  to  allow  of  large  chambers. 
The  ore  is  obtained  at  a  depth  of  about  750  fret,  and  is  mostly  a  bitu- 
minous cinnabar,  disseminated  through  the  rock  along  with  native  mer- 
cury. The  latter  is  in  some  parts  so  abundant  that  when  the  earthy 
rock  is  fresh  broken,  large  globules  fall  out  and  roll  to  the  bottom  of  the 
gallery.  The  pure  mercury  is  first  sifted  out ;  the  gangue  is  then 
washed,  and  prepared  for  reduction.  For  this  purpose  there  is  a  large 
circular  building,  40  feet  in  diameter  by  60  in  height,  the  interior  of 
which  communicates  through  small  openings  with  a  range  of  chambers 
around,  each  10  or  12  feet  square,  and  having  a  door  communicating 
with  the  external  air.  The  central  chamber  is  filled  with  earthen  pans, 
containing  the  prepared  earth,  the  whole  is  closed  up  and  heat  is  ap- 
plied. The  mercury  sublimes  and  is  condensed  in  the  cold  air  of  the 
smaller  chambers,  whence  it  is  afterwards  removed.  After  filtering,  it 
is  ready  for  packing.  These  mines  afford  annually  3000  cwt. 

The  above  mode  of  reduction  is  styled  by  Ure  "  absolutely  barba- 
rous." He  observes  that  the  brick  and  mortar  walls  cannot  be  ren- 
dered either  tight  or  cool  ;  and  that  the  ore  ought  to  be  pounded,  and 
then  heated  in  a  series  of  cast-iron  cylinder  retorts,  after  being  mixed 
with  the  requisite  proportion  of  quicklime,  (the  lime  aiding  in  the  re- 
duction of  the  cinnabar  by  taking  its  sulphur,)  and  the  retorts  should 
communicate  with  a  trough  through  which  a  stream  of  water  passes, 
for  the  purpose  of  condensing  the  mercury.  An  apparatus  of  this  kind 
planned  by  Ure,  is  used  at  Land&berg,  in  Rhenish  Bavaria. 

The  mines  of  the  Palatinate,  on  the  Rhine,  and  those  of  other  parts 
of  Germany,  are  stated  by  Burat  to  yield  7.600  quintals. 

The  mines  of  Almaden  are  situated  near  the  frontier  of  Estremadu- 
ra,  in  the  province  of  La  Mancha.  They  have  been  worked  from  a 
remote  antiquity.  According  to  Pliny,  the  Greeks  obtained  vermillion 
from  them  700  years  before  our  era,  and  afterwards  imported  annually 
100,000  pounds.  The  mines  are  not  over  300  yards  in  depth,  although 
so  long  worked.  The  rock  is  argillaceous  schist  and  grit,  in  horizontal 
beds,  which  are  inteisected  by  granitic  and  black  porphyry  eruptions. 
The  mass  of  ore  at  the  bottom  of  the  principal  vein,  is  12  to  15  yards 
thick,  and  yields  in  the  aggregate  10  per  cent,  of  mercury.  It  is  taken 
to  the  furnace  without  any  kind  of  mechanical  preparation.  There  are 
many  veins  in  the  vicinity,  several  of  which  have  been  explored.  The 
furnaces  of  Almadenejos  are  fed  almost  exclusively  by  an  ore  obtained 
just  east  of  the  village,  which  is  a  black  schist,  strongly  impregnated 


What  is  said  of  the  Idria  mines  ?     How  is  the  ore  reduced  ?     What 
is  a  better  process  ]     What  is  said  of  the  mines  of  Almaden  ? 


COPPER    ORES.  273 

with  native  mercury  and  cinnabar,  with  but  little  visible.  These  mines 
afford  annually  about  20.000  cwt.  of  mercury.  The  granitic  and  por- 
phyritic  eruptions  of  the  region  have  been  supposed  to  account  for  the 
presence  of  the  mercury  in  the  rocks :  the  heat  produced  exhalations 
of  mercury  and  sulphur,  which  gave  origin  both  to  the  cinnabar  and  the 
native  mercury. 

The  mines  of  Huanca  Velica,  in  Peru,  have  afforded  a  large  amount 
of  mercury  for  amalgamation  at  the  Peruvian  silver  mines.  Between 
the  years  1570  and  1800,  they  are  estimated  to  have  produced  537.000 
tons  ;  and  their  present  annual  yield  is  1800  quintals. 

The  Chinese  have  mines  of  cinnabar  in  Shensi,  where  the  ore  is  re- 
duced by  the  rude  process  of  burning  brushwood  in  the  wells  or  pits 
dug  out  for  the  purpose,  and  then  collecting  the  metal  after  condensa- 
tion. 

14.    COPPER. 

Copper  occurs  native  in  considerable  quantities ;  also 
combined  with  oxygen,  sulphur,  selenium,  and  various  acids. 

The  ores  of  copper  vary  in  specific  gravity  from  3*5  to  8*5, 
and  seldom  exceed  4  in  hardness.  Many  of  the  ores  give  to 
borax  a  green  color  in  the  outer  flame,  and  an  opaque  dull- 
red  in  the  inner.  With  carbonate  of.  soda  on  charcoal, 
nearly  all  the  ores  are  reduced,  and  a  globule  of  copper  ob- 
tained ;  borax  and  tin  foil  are  required  in  some  cases  where 
a  combination  with  other  metals  conceals  the  copper.  When 
soluble  in  the  acids,  a  clean  plate  of  iron  inserted  in  the  so- 
lution becomes  covered  with  copper,  and  ammonia  produces 
a  blue  solution. 

NATIVE    COPPER. 

Monometric.  In  octahedrons ;  no  cleavage  apparent. 
Often  in  plates  or  masses,  or  arborescent  and  filiform  shapes. 

Color  copper-red.  Ductile  and  malleable.  H=2'5 — 3. 
Gr==8-58. 

Native  copper  often  contains  a  little  silver,  disseminated 
throughout  it.  Before  the  blowpipe  it  fuses  readily,  and  on 
cooling  it  is  covered  with  a  black  oxyd.  Dissolves  in  ni- 
tric acid,  and  produces  a  blue  solution  w'th  ammonia. 

Obs.  Native  copper  accompanies  the  ores  of  copper,  and 
usually  occurs  in  the  vicinity  of  dikes  of  igneous  rocks. 

How  does  copper  occur  1  How  are  copper  ores  distinguished  ?  What 
are  the  characters  of  native  copper] 


274  METALS* 

Siberia,  Cornwall,  and  Brazil,  are  noted  for  the  copper 
they  have  produced.  A  mass  supposed  to  be  from  Bahia, 
now  at  Lisbon,  weighs  2616  pounds.  The  vicinity  of  lake 
Superior  is  one  of  the  most  extraordinary  regions  in  the 
world  for  its  native  copper,  where  it  occurs  mostly  in  ver- 
tical seams  in  trap,  and  also  in  the  enclosing  sandstone.  A 
mass  weighing  3704  Ibs.  has  been  taken  from  thence  to  Wash- 
ington city  :  it  is  the  same  that  was  figured  by  Schoolcraft, 
in  the  American  Journal  of  Science,  volume  iii,  p.  201. 
Masses  from  1000  to  3700  pounds,  from  this  region,  have 
been  exposed  on  the  wharves  of  Boston,  Mass.  This  is 
small  compared  with  other  pieces  which  have  since  been 
laid  open.  One  large  mass  was  quarried  out  in  the  "  Cliff 
mine,"  whose  weight  has  been  estimated  at  80  tons.  It  was 
50  feet  long,  6  feet  deep,  and  averaged  6  inches  in  thickness. 
This  copper  contains  intimately  mixed  with  it  about  T3¥  per 
cent,  of  silver.  Besides  this,  perfectly  pure  silver,  in  strings, 
masses,  and  grains,  is  often  disseminated  through  the  cop- 
per, and  some  masses,  when  polished,  appear  sprinkled  with 
large  white  spots  of  silver,  resembling,  as  Dr.  Jackson  ob- 
serves, a  porphyry  with  its  feldspar  crystals.  Crystals 
of  native  copper  are  also  found  penetrating  masses  of  preh- 
nite,  and  analcime,  in  the  trap  rock. 

This  mixture  of  copper  and  silver  cannot  be  imitated  by 
art,  as  the  two  metals  form  an  alloy  when  melted  together. 
It  is  probable  that  the  separation,  in  the  rocks,  is  due  to  the 
cooling  from  fusion  being  so  extremely  gradual  as  to  allow 
the  two  metals  to  solidify  separately,  a,t  their  respective 
temperatures  of  solidification — the  trap  being  an  igneous 
rock,  and  ages  often  elapsing,  as  is  well  known,  during  the 
cooling  of  a  bed  of  lava,  covered  from  the  air. 

Small  specimens  of  native  copper  have  been  found  in  the 
states  of  New  Jersey,  Connecticut,  and  Massachusetts,  where 
the  same  formation  occurs.  One  mass  from  near  Somerville 
weighs  78  pounds,  and  is  said  originally  to  have  weighed 
128  pounds.  Near  New  Haven,  Conn.,  a  mass  of  90  pounds 
was  formerly  found.  Near  Brunswick,  N.  J.,  a  vein  or  sheei 
of  copper,  from  a  sixteenth  to  an  eighth  of  an  inch  thick, 
has  been  observed  and  traced  along  for  several  rods. 


Where  has  native  copper  been  found  in  the  United  States  ?  What 
is  said  of  its  associations  with  silver  ]  What  explanation  is  given  of 
this  mixture  of  copper  and  silver  I 


COPPER  ORES.  275 


VITREOUS  COPPER  ORE. 

Trimetric.  Cleavage  parallel  to  the  faces  of  a  right  rhom- 
bic prism,  but  indistinct.  M  :  M=1191  35'.  Secondary 
forms,  variously  modified  rhombic  prisms.  Also  in  com- 
pound crystals  like  arragonite  ;  often  massive. 

Color  and  streak  blackish  lead-gray,  often  tarnished  blue 
or  green.  Streak  sometimes  shining.  H=2'5 — 3.  Gr= 
5.5—5.8. 

Composition :  sulphur  20'6,  copper  77-2,  iron  1-5.  Be- 
fore  the  blowpipe  it  gives  off  fames  of  sulphur,  fuses  easily 
in  the  external  flame,  and  boils.  After  the  sulphur  is  driven 
off,  a  globule  of  copper  remains.  Dissolves  in  heated  nitric 
acid,  with  a  precipitation  of  the  sulphur. 

Dif.  The  vitreous  copper  ore  resembles  vitreous  sil- 
ver ore  ;  but  the  luster  of  a  surface  of  fracture  is  less  bril- 
liant, and  they  afford  different  results  before  the  blowpipe. 
The  solution  made  by  putting  a  piece  of  the  ore  in  nitric 
acid,  covers  an  iron  plate  (or  knife  blade)  with  copper,  while 
a  similar  solution  of  the  silver  ore  covers  a  copper  plate 
with  silver. 

Obs.  Occurs  with  other  copper  ores  in  beds  and  veins. 
At  Cornwall,  splendid  crystallizations  occur.  Siberia,  Hesse, 
Saxony,  the  Bannat,  Chili,  &c.,  afford  this  ore. 

In  the  United  States,  a  vein  affording  fine  crystallizations 
occurs  at  Bristol,  Conn.  Other  localities  are  at  Wolcott- 
ville,  Simsbury,  and  Cheshire,  Conn.  ;  at  Schuyler's  Mines, 
and  elsewhere,  N.  J. ;  in  the  U.  S.  copper  mine  district, 
Blue  Ridge,  Orange  county,  Virginia  ;  between  New  Mark- 
et and  Taneytown,  Maryland  ;  and  sparingly  at  the  copper 
,  mines  of  Michigan  and  the  Western  states  ;  abundantly  at 
some  mines  north  of  Lake  Huron. 

Blue  Copper  is  a  dull  blue-black  massive  mineral.  Gr=3'8 — .  It 
contains  65  per  cent,  of  copper. 

Digenite  is  a  dark  lead-gray  sulphuret  containing  70'2  per  cent,  of 
copper.  Gr=4'6 — 4'68.  Streak  black.  From  Chili,  and  also  Thu- 

ringia. 

COPPER  PYRITES. — SuJphuret  of  Copper  and  Iron. 
Dimetric.     Crystals  tetrahedral  or  octahedral ;  sometimes 


What  are  the  physical  characters  of  vitreous  copper  1  its  constitution 
and  chemical  characters  ?     How  does  it  differ  from  silver  ores  ? 


276  META1S. 

compound.     A  :  A=109°  53',  and  108°  40'.     Cleavage  in- 
distinct.   Also  massive,  2 
and  of  various  imitative             /^^\ 
shapes.                                      /      7    X 

Color  brass-yellow, 
often  tarnished  deep  yel- 
low, and  also  iridescent. 
Streak  unmetallic,  greenish-black,  and 
but  little  shining.  H==3*5 — 4.  Gr= 
4-15— 4-17. 

Composition  :  sulphur  36*3,  copper 
32*1,  iron  31*5.  Fuses  before  the  blowpipe  to  a  globule 
which  is  magnetic,  owing  to  the  iron  present.  Gives  sul- 
phur fumes  on  charcoal.  With  borax  affords  pure  copper. 
The  usual  effect  with  nitric  acid. 

Dif.  This  ore  resembles  native  gold,  and  also  iron  py- 
rites. It  is  distinguished  from  gold  by  crumbling  when  it  is 
attempted  to  cut  it,  instead  of  separating  in  slices  ;  and  from 
iron  pyrites  in  its  deeper  yellow  color  and  in  yielding  easily 
to  the  point  of  a  knife,  instead  of  striking  fire  with  a  steel. 

Obs.  Copper  pyrites  occurs  in  veins  in  granitic  and  al- 
lied rocks  ;  also  in  graywacke,  &c.  It  is  usually  associated 
with  iron  pyrites,  and  often  with  galena,  blende,  and  carbon- 
ates of  copper.  The  copper  of  Fahlun,  Sweden,  is  obtained 
mostly  from  this  ore,  where  it  occurs  with  serpentine  in 
gneiss.  Other  mines  of  this  ore  are  in  the  Hartz,  near 
Goslar;  in  the  Bannat,  Hungary,  Thuringia,  &c.  The 
Cornwall  ore  is  mostly  of  this  kind,  and  10  to  12,000  tons 
of  pure  copper  are  smelted  annually.  The  ore  for  sale  at 
Redruth  is  said  to  be  by  no  means  a  rich  ore.  It  rarely 
yields  12  per  cent,  and  generally  only  7  or  8,  and  occasion- 
ally as  little  as  3  to  4  per  cent,  of  metal.  In  the  latter  case 
such  poverty  of  ore  is  only  made  up  by  its  facility  of  trans- 
port, the  moderate  expense  of  fuel,  or  the  convenience  of 
smelting.  Its  richness  may  generally  be  judged  of  from  the 
color  :  if  of  a  fine  yellow  hue,  and  yielding  readily  to  the 
hammer,  it  is  a  good  ore  ;  but  if  hard  and  pale  yellow  it  con- 
tains very  largely  of  iron  pyrites,  and  is  of  poor  quality. 
In  the  United  States  there  are  many  localities  of  this  ore. 

What  forms  are  presented  by  copper  pyrites  1     What  is  its  color  and 
streak  1  its  composition?     How  is  it  distinguished  from  iron  pyrites  and 
gold  1     What  is  said  of  the  modes  of  occurrence  of  this  ore  and  of  it 
mines  1 


COf'l'EK    QRES.  277 

It  occurs  in  Massachusetts,  at  the  Southampton  lead  mines, 
at  Turner'*  Falls  on  the  Connecticut,  at  Hatfield  and  Ster- 
ling ;  in  Vermont,  at  Straffbrd,  where  it  is  now  profitably 
worked,  and  at  Shrewsbtiry,  Corinth,  Waterbury ;  in  New 
Hampshire,  at  Franconia,  Sheiburn,  Unity,  Warren,  Eaton, 
Lyme,  Havcrhill ;  in  Maine,  at  the  Lubec  lead  mines,  and 
Plater ;  in  New  York,  at  the  Ancram  lead  mine,  also  near 
Rossie,  and  at  Wurtzboro  ;  in  Pennsylvania,  at  Mcrgantown  ; 
in  Virginia,  at  the  Phenix  copper  mines,  Fauquier  county, 
and  at  the  Walton  gold  mine,  Luzerne  county  ;  in  Maryland, 
in  the  Catoctin  mountains,  between  Newmarket  and  Taney- 
town  ;  in  North  Carolina,  in  Davidson  and  Guilfbrd  coun- 
ties. In  Michigan,  where  native  copper  is  so  abundant,  this 
is  a  rare  ore  ;  but  it  occurs  at  Presque  isle,  at  Mineral  Point, 
and  in  Wisconsin,  where  it  is  the  predominating  ore. 

The  ore  of  Strafford,  Vt.,  is  at  the  present  time  carried  to 
Boston. 

Uses.  This  ore,  besides  being  mined  for  copper,  is  ex- 
tensively employed  in  the  manufacture  of  blue  vitriol  (sul- 
phate of  copper.)  in  the  same  manner  that  sulphate  of  iron 
(copperas)  is  obtained  from  iron  pyrites. 

Cuban  is  a  sulphuret  of  copper  and  iron,  containing  sulphur  34'8, 
iron  42'5,  copper  23  0. 

VARIEGATED    COPPER    PYRITES. 

Monometric.  Cleavage  octahedral,  in  traces.  Occurs  in 
cubes  and  octahedrons.  Also  massive. 

Color  between  copper-red  and  pmehbeck-brown.  Tar- 
nishes rapidly  on  exposure.  Streak  pale  grayish-black  and 
but  slightly  shining.  Brittle.  H=3.  Gr=5. 

Composition  :  specimen  from  Bristol,  Conn.,  sulphur  25'7, 
copper  G2'8,  iron  11 '6.  Fuses  before  the  blowpipe  to  a 
globule  attractable  by  the  magnet.  On  charcoal  affords 
names  of  sulphur.  Mostly  dissolved  in  nitric  acid. 

Dif.  This  ore  is  distinguished  from  the  preceding  by  its 
pale  reddish-yellow  color. 

Obs.  Occurs  with  other  copper  ores,  in  granitic  and  al- 
lied rocks,  and  also  in  secondary  formations.  The  mines 
of  Cornwall  have  afforded  crystallized  specimens,  and  it  is 
there  called  from  its  color  "  horse-flesh  ore."  Other  foreign 

What  is  the  appearance  and  composition  of  variegated  copper  py- 
rites ?     How  is  it  distinguished  from  the  preceding  species  ] 
•24 


278  METALS. 

localities  of  massive  varieties  are  Ross  Island,  Rillarney, 
Ireland  ;  Norway,  Hessia,  Silesia,  Siberia,  and  the  Bannat. 
Fine  crystallizations  occur  at  the  Bristol  copper  mine, 
Conn.,  in  granite  ;  and  also  in  red  sandstone,  at  Cheshire,  in 
the  same  state,  with  malachite  and  heavy  spar.  Massive  va- 
rieties occur  at  the  New  Jersey  mines,  and  in  Pennsylvania. 

GRAY    COPPER    ORE. 

Monometric.  Occurs  in  modified  tetrahedrons,  and  also 
in  compound  crystals.  Cleavage  octahedral  in  traces. 

Color  between  steel-gray  and 
iron-black.  Streak  nearly  as  the 
color.  Rather  brittle.  H— 3 — 
4.  Gr=4-75— 5-1. 

Composition :  sulphur  26*3, 
copper  38'6,  antimony  16'5,  arsenic  7-2,  along  with  some 
iron,  zinc,  and  silver,  amounting  to  15  per  cent.  It  some- 
times  contains  30  per  cent,  of  silver  in  place  of  part  of  the 
copper,  and  is  then  called  argentiferous  gray  copper  ore,  or 
silver  fahlerz.  The  amount  of  arsenic  varies  from  0  to  10 
per  cent.  One  variety  from  Spain  included  10  per  cent,  of 
platinum,  and  another  from  Hohenstein  some  gold  ;  another 
from  Tuscany  2'7  per  cent,  of  mercury. 

These  varieties  give  off,  before  the  blowpipe,  fumes  of  ar- 
senic and  antimony,  and  after  roasting  yield  a  globule  of  cop- 
per. Dissolve,  when  pulverized,  in  nitric  acid,  affording  a 
brownish-green  solution. 

Dif.  Its  copper  reactions  before  the  blowpipe  and  in  so- 
lution  in  nitric  acid,  distinguish  it  from  the  gray  silver  ores. 

Obs.  The  Cornish  mines,  Andreasberg  in  the  Hartz, 
Kremnitz  in  Hungary,  Freiberg  in  Saxony,  Kapnik  in 
Transylvania,  and  Dillenberg  in  Nassau,  afford  fine  crystal- 
lizations  of  this  ore.  It  is  a  common  ore  in  the  Chilian 
mines,  and  it  is  worked  there  and  elsewhere  for  copper,  and 
often  also  for  silver. 

Bournonite  contains  sulphur  20'3,  antimony  26'3,  lead  40'8,  cop 
12.7.  Its  crystals  are  modified  rectangular  prisms,  of  a  steel-gray  colon 
and  streak,  and  are  often  compounded  into  shapes  like  a  cog-wheel, 
whence  it  is  called  wheel-ore.  H=2  5 — 3.  Gr=5'766.  From  the 
Hartz,  Transylvania,  Saxony,  and  Cornwall.  Another  allied  ore,  con- 
taining 47  per  cent,  of  antimony,  is  called  antimonial  copper;  it  oc- 

Describe  gray  copper  ore.  Mention  its  composition  and  blowpipe 
characters.  How  is  it  distinguished  from  silver  ores  1 


COPPER    ORES.  279 


cars  in  slender  aggregated  prisms,  of  a  dark  lead-gray  color.  Another 
containing  also  arsenic,  is  called  antimonial  copper  glance. 

Tennantitc  is  a  compound  of  copper,  iron,  sulphur,  and  arsenic.  It 
occurs  in  dodecahedral  crystals,  brilliant,  with  a  dark  lead-gray  color, 
and  reddish-gray  streak.  From  the  Cornish  mines  near  Redruth  and 
St.  Day. 

Selenid  of  Copper,  is  a  silver-white  ore,  affording  the  horse-radish 
odor  of  selenium  before  the  blowpipe.  It  contains  64  per  cent,  of  cop- 
per. From  Skrikerum,  Sweden. 

RED    COPPER    ORE. 

Monometric.     In  regular  octahedrons,  and  modified  forms 
of  the  same.     Cleavage    octahedral.     Also   massive,   and 
sometimes  earthy. 

Color    deep   red,    of   various 
shades.      Streak    brownish-red. 
Luster  adamantine  or  submetal- 
lic  ;  also    earthy.      Subtranspa- 
rent  to  nearly  opaque.     Brittle. 
H=3-5— 4.     Gr=6. 
Composition  :  copper  88*88,  oxygen  12.     Before  the  blow- 
pipe, on  charcoal,  it  yields  a  globule  of  copper.     Dissolves 
in  nitric  acid.     The  earthy  varieties  have  been  called  tile 
ore,  from  the  color. 

Dif.  From  cinnabar  it  differs  in  not  being  volatile  before 
the  blowpipe  ;  and  from  red  iron  ore,  in  yielding  a  bead  of 
copper  on  charcoal,  and  copper  reactions. 

Obs.  Occurs  with  other  copper  ores  in  the  Bannat,  Thur- 
ingia,  Cornwall,  at  Chessy  near  Lyons,  in  Siberia,  and  Bra- 
zil. The  octahedrons  are  often  green,  from  a  coating  of 
malachite. 

In  the  U.  States,  it  has  been  observed  crystallized  and 
massive,  at  Schuyler's,  Somerville,  and  the  Flemington  cop- 
per mines,  N.  J. ;  also  near  New  Brunswick,  N.  J.  ;  at 
Bristol,  Ct. ;  also  near  Ladenton,  Rockland  county,  N.  Y. 

Black  Copper.  Tenorite.  An  oxyd  of  copper,  occurring 
as  a  black  powder  and  in  dull  black  masses,  and  botryoidal 
concretions,  in  veins  or  along  with  ether  copper  ores-  From 
Cornwall,  and  also  the  Vesuvian  lavas.  It  is  an  abundant 
ore  in  some  of  the  copper  mines  of  the  Mississippi  valley, 
and  yields  60  to  70  per  cent,  of  copper.  But  part  of  what 

What  is  the  crystallization  of  red  copper  ore  ?  Of  what  does  it  con* 
Bis;  i  How  does  it  differ  from  cinnabar  and  red  iron  ore? 


280  METALS. 

•was  considered  black  copper  in  the  west  is  an  ore  of  cobalt. 
If  absolutely  pure,  it  contains  80  per  cent,  of  copper.  It  is 
also  found  of  excellent  quality  in  large  veins,  in  the  Lake 
Superior  copper  region. 

The  oxyds  of  copper  are  easily  smelted  by  heating  with 
the  aid  of  charcoal  alone.  They  may  be  converted  directly 
into  the  sulphate  or  blue  vitriol,  by  means  of  sulphuric  acid, 
but  are  more  valuable  for  the  copper  they  afford. 


BLUE    VITRIOL.  -  SlllpkatC  of 

Triclinate.  In  oblique  rhomboidal  prisms.  Also  as  au 
efflorescence  or  incrustation. 

Color  deep  sky-blue.  Streak  uncolored,  Subtransparent 
to  translucent,  Luster  vitreous.  Soluble,  taste  nauseous 
and  metallic.  H=2  —  2-5.  Gr=2-2U 

Composition:  sulphuric  acid  31'7,  oxyd  of  copper,  32*1, 
water  36-2.  A  polished  plate'  of  iron  in  a  solution  becomes 
covered  with  copper. 

Obs.  Occurs  with  the  sulphurets  of  copper  as  a  result  of 
their  decomposition,  and  is  often  in  solution  in  the  waters 
flowing  from  copper  mine?.  Occurs  in  the  Hartz,  at  Fahlun 
in  Sweden,  and  in  many  other  copper  regions. 

Uses.  Blue  vitriol  is  much  used  in  dyeing  operations  and 
in  the  printing  of  cotton  and  linen  ;  also  for  various  other 
purposes  in  the  ails.  It  has  been  employed  to  prevent  dry 
rot,  by  steeping  wood  in  its  solution  :  and  it  is  a  powerful 
preservative  of  animal  substances  ;  when  imbued  with  it  and 
dried,  they  remain  unaltered.  It  is  afforded  by  the  decom- 
position of  copper  pyrites,  in  the  same  manner  as  green  vit- 
riol from  iron  pyrites,  (p.  213.) 

It  is  manufactured  for  the  arts  from  old  sheathing  copper, 
copper  turnings,  and  copper  refinery  scales.  The  scales  are 
readily  dissolved  in  dilute  sulphuric  acid  at  the  temperature 
of  ebullition  ;  the  solution  obtained  is  evaporated  to  the  point 
where  crystallization  will  take  place  on  cooling.  Me  allic 
copper  is  exposed  in  hot  rooms  to  the  atmosphere  after  it  has 
been  wet  in  weak  sulphuric  acid.  ]$y  alternate  wetting  and 
exposure,  it  is  rapidly  corroded,  and  affords  a  solution  which 


What  is  blue  vitriol  1  Describe  it.  What  is  said  of  its  mode  of  oc- 
currence ?  For  what  is  it  used  ?  How  ie  it  manufactured  in  the  arts? 
How  is  copper  obtained  from  solutions  iu  some  mines  ?  Describe 
green  malachite. 


COPPER    ORES.  281 

is  evaporated  for  crystals.  400,000  Ibs.  is  the  annual  con- 
sumption of  blue  vitriol  in  the  United  States. 

In  Frederick  county,  Maryland,  blue  vitriol  is  made  from 
a  black  earth  which  is  an  impure  oxyd  of  copper  with  cop- 
per pyrites.  The  black  oxyd  of  copper,  which  was  found 
in  the  Lake  Superior  copper  region,  may  be  directly  con- 
verted into  blue  vitriol. 

In  some  mines,  the  solution  of  sulphate  of  copper  is  so 
abundant  as  to  afford  considerable  copper,  which  is  obtained 
by  immersing  clean  iron  in  it,  and  is  called  copper  of  cemen- 
tation. At  the  copper  springs  of  Wicklow,  Ireland,  about  500 
tons  of  iron  were  laid  at  one  time  in  the  pits  ;  in  about  12 
months  the  bars  were  dissolved,  and  every  ton  of  iron  yielded 
a  ton  and  a  half,  and  sometimes  nearly  two  tons,  of  a  pre- 
cipitated reddish  mud,  each  ton  of  which  produced  16  cwt. 
of  pure  copper.  The  Rio  Tinto  Mine  in  Spain,  is  another 
instance  of  working  the  sulphate  in  solution.  These  waters 
yield  annually  1800  cwt.  of  copper,  and  consume  2400  cwt. 
of  iron. 

Brochantite.  An  insoluble  sulphate  of  copper,  containing  17'5  per 
cent,  of  sulphuric  acid.  Color  emerald  green.  In  tabular  rhombic  crys- 
tals, at  Katherinenberg,  in  Siberia.  Blackens  before  the  blowpipe  with- 
out fusing.  Krisuvigiie  and  Konigite  are  the  same  species. 

GREEN  MALACHITE. — Green  Carbonate  of  Copper. 

Monoclinate.  Usual  in  incrustations,  with  a  smooth  tube- 
botryoidal  or  stalactitic  surface  ;  structure  finely  and 
firmly  fibrous.  Also  earthy. 

Color  light  green,  streak  paler.  Usually  nearly  opaque ; 
crystals  translucent.  Luster  of  crystals  adamantine  incli- 
ning to  vitreous  ;  but  fibrous  incrustations  silky  on  a  cross 
fracture.  Earthy  varieties  dull.  H=3*5 — 4.  Gr=4. 

Composition:  carbonic  acid  18,  oxyd  of  copper  70'5,  wa- 
ter 11 '5.  Dissolves  with  effervesence  in  nitric  acid.  De- 
crepitates and  blackens  before  the  blowpipe,  and  becomes 
partly  a  black  scoria.  With  borax  it  fuses  to  a  deep  green 
globule,  and  ultimately  affords  a  bead  of  copper. 

Dif.  Readily  distinguished  by  its  copper-green  color  and 
its  association  with  copper  ores.  It  resembles  a»siliceous 
ore  of  copper,  chrysocolla,  a  common  ore  in  the  mines  of 
the  Mississippi  valley  ;  but  it  is  distinguished  by  its  complete 

What  is  the  composition  of  green  malachite  ?  How  is  it  distin- 
guished ? 

24* 


282  METALS. 

solution  and  effervescence  in  nitric  acid.  The  color  also 
is  not  the  bluish-green  of  chrysocolla. 

Obs.  Green  malachite  usually  accompanies  other  ores 
of  copper,  and  forms  incrustations,  which  when  thick,  have 
the  colors  banded  and  extremely  delicate  in  their  shades  and 
blending.  Perfect  crystals  are  quite  rare.  The  mines  of 
Siberia,  at  Nischne  Tagilsk,  have  afforded  great  quantities 
of  this  ore.  A  mass  partly  disclosed,  measured  at  top  9 
feet  by  18  ;  and  the  portion  uncovered  contained  at  least 
half  a  million  pounds  of  pure  malachite.  Other  noted  for- 
eign localities  are  Chessy  in  France,  Sandlodge  in  Shetland, 
Schwartz  in  the  Tyrol,  Cornwall,  and  the  island  of  Cuba. 

The  copper  mine  of  Cheshire,  Conn.,  has  afforded  hand- 
some specimens  ;  also  Morgantown,  and  the  Perkiomen  Lead 
Mine,  Penn. ;  Schuyler's  mine,  and  the  New  Brunswick 
copper  mine,  N.  J.  :  it  occurs  also  in  Maryland,  between 
Newmarket  and  Taneytown,  and  in  the  Catoctin  mountains  ; 
in  the  Blue  Ridge,  Penn.,  near  Nicholson's  Gap,  and  it  is 
found  more  or  less  sparingly  with  all  kinds  of  copper  ores. 

At  Mineral  Point,  Wisconsin,  a  bluish  silico-carbonate 
of  copper  occurs,  which  is  for  the  most  part  chrysocolla,  or 
a  mixture  of  this  mineral  with  the  carbonate.  An  analysis 
of  the  rough  ore  afforded  Mr.  D.  D.  Owen,  copper  35-7, 
carbonic  acid  10*0,  water  10*0,  iron  15*7,  oxygen  7,  sulphur 
8,  silex  13-0.  Specific  gravity  3-69—3-87.  The  vein  ap- 
pears also  to  the  northwest  on  Blue  River,  and  southeast  on 
the  Peccatonica.  This  ore  is  abundant ;  it  has  been  smelted 
on  the  spot  and  also  exported  to  England. 

Uses.  This  mineral  receives  a  high  polish  and  is  used 
for  inlaid  work,  and  also  ear-rings,  snuffboxes,  and  various 
ornamental  articles.  It  is  not  much  prized  in  jewelry. 
Very  large  masses  are  occasionally  obtained  in  Russia, 
which  are  worked  into  slabs  for  tables,  mantel-pieces  and 
vases,  which  are  of  exquisite  beauty,  owing  to  the  delicate 
shadings  of  the  radiations  and  zones  of  color.  At  Versailles, 
there  is  a  room  furnished  with  tables,  vases,  and  other  arti- 
cles of  this  kind,  and  similar  rooms  are  to  be  found  in  many 
European  palaces.  At  Nischne  Tagilsk,  a  block  of  mala- 
chite w«,s  obtained  weighing  40  tons. 

Malachite  is  sometimes  passed  off  in  jewelry  as  turquois, 
though  easily  distinguished  by  its  shade  of  color  and  much 

How  does  green  malachite  occur  1     What  are  its  uses  ? 


COPPER   ORES.  283 

inferior  hardness.  It  is  a  valuable  ore  when  abundant ;  but 
it  is  seldom  smelted  alone,  because  the  metal  is  liable  to  es- 
cape with  the  liberated  volatile  ingredient — carbonic  acid. 

AZTJRITE. — Blue  Carbonate  of  Copper. 

Monoclinate.     In  modified  oblique  rhombic   prisms,  the 
crystals  rather  short  and  stout  $ 
lateral  cleavage    perfect.     Also 
massive.     Often  earthy. 

Color  deep  blue,  azure  or  Ber- 
lin-blue. Transparent  to  nearly 
opaque.  Streak  bluish*  Luster 
vitreous,  almost  adamantine. — 
Brittle,  H=3-5— 4-5.  Gr= 
3-5—3-85. 

Composition :  carbonic  acid  25*5,  oxyd  of  copper  69.1, 
water  5*5.  Before  the  blowpipe  and  in  acids,  it  acts  like 
the  preceding. 

Obs.  Azurite  accompanies  other  ores  of  copper.  At 
Chessy,  France,  its  crystallizations  are  very  splendid.  It  is 
found  also  in  Siberia,  in  the  B  a  mi  at,  and  near  Redruth  in 
Cornwall. 

As  incrustations  and  rarely  as  crystals,  it  occurs  near 
Singsing,  N.  Y. ;  near  New  Brunswick,  N.  J.  Also  near 
Nicholson's  Gap,  in  the  Blue  Ridge,  Penn. 

Uses.  When  abundant  it  is  a  valuable  ore  of  copper.  It 
makes  a  poor  pigment,  as  it  is  liable  to  turn  green. 

CHRYSOCOLLA. — Silicate  of  Copper. 

Usually  as  incrustations ;  botryoidal  and  massive.  Also 
in  thin  seams  and  stains  ;  no  fibrous  structure  apparent,  nor 
any  appearance  of  crystallization. 

Color  bright  green,  bluish-green.  Luster  of  surface  of  in- 
crustations smoothly  shining  ;  also  earthy.  Translucent  to 
opaque.  H=2 — 3.  Gr  =  2 — 2*3.  Composition:— 


SIBERIAN. 

V.  Kobell. 

NEW  JERSEY. 

Berthier.        Bowen. 

Beck. 

Oxyd  of  copper 

40-0 

55-1 

452 

426 

Silica 

36-5 

35-4 

373 

40-0 

Water 

20-2 

28-5 

17-0 

16-0 

Carbonic  acid 

2-1 

loss           1-0 

. 

—  . 

Oxyd  of  iron 

1-0 





1-4 

Describe  blue  malachite.  How  does  it  differ  from  green  malachite 
in  composition  ]  What  is  the  appearance  of  chrysocolla  1  its  composi- 
tion? 


284  HETACSV 

The  mineral  varies  much  in  the  proportion  of  its  constitu- 
ents, as  it  is  not  crystallized.  It  blackens  in  the  mner  flame 
of  the  blowpipe  without  melting.  With  borax  it  is  partly 
reduced.  No  effervescence  nor  complete  solution  in  nitric 
acid,,  cold  or  heated. 

Dif.  Distinguished  from  green  malachite  as  stated  under 
that  species. 

Obs.  Accompanies  other  copper  ores  in  Cornwall,  Hun- 
gary, the  Tyrol,  Siberia,  Thuringia,  &c.  In  Chili  it  is 
abundant  at  the  various  mines.  In  Wisconsin  and  Missouri 
it  is  so  abundant  as  to  be  worked  for  copper-  It  was  for- 
merly taken  for  green  malachite.  It  also  occurs  at  the  Som- 
erville  and  Schuyler's  mine,  N.  J.,  at  Morgantown,  Penn., 
and  Wolcotville,  Conn. 

Uses.  This  ore  in  the  pure  state  affords  30  per  cent,  of 
copper ;  but  as  it  occurs  in  the  rock  will  hardly  yield  one- 
third  this  amount.  Still  when  abundant,  as  it  appears  to  be 
in  the  Mississippi  valley,  it  is  a  valuable  ore.  It  is  easy  of 
reduction  by  means  of  limestone  as  a  ffux. 

Dioptase  is  another  silicate  of  copper,  occurring  in  rhonabohedral 
crystals  and  hexagonal  prisms.  R  :  R=126°  17".  Color  emerald- 
green.  Luster  vitreous.  Streak  greenish.  Transparent  to  nearly 
opaque.  H=5.  Gr=3'28.  From  the  Kirghese  Steppes  of  Siberia. 

Besides  the  above  salts  of  copper,  there  are  the  following  species, 
which  are  of  little  use  in  the  arts. 

Ar senates  of  Copper. — Euchroite  has  a  bright  emerald -green  color, 
and  contains  33  per  cent,  of  arsenic  acid,  and  48  of  oxyd  of  copper. 
Occurs  in  modified  rhombic  prisms.  H=3'75.  Gr=3  4.  From  Li- 
bethen,  in  Hungary.  Aphanesite  is  of  a  dark  verdigris-green  inclining 
to  blue,  and  also  dark  blue,  H=2  5— 3.  Gr=4'19.  It  contains  30 
per  cent,  of  arsenic  acid  and  54  of  oxyd  of  copper.  From  Cornwall. 
Erinite  has  an  emerald-green  color,  and  occurs  in  mammilated  coat- 
ings. H=4'5 — 5.  Gr=4'04.  Contains  338  of  arsenic  acid  and  59'4 
of  oxyd  of  copper.  From  Limerick,  Ireland,  Liroconite  varies  from 
eky-blue  to  virdigris-green,  It  occurs  in  rhombic  prisms,  sometimes 
an  inch  broad.  H=2'5.  Gr=2'8— 2  9.  Contains  14  per  cent,  of 
arsenic  acid,  49  of  oxyd  of  copper.  Olivenite  presents  olive-green  to 
brownish  colors,  and  occurs  in  prismatic  crystals  or  velvety  coatings. 
H=3.  Gr=4'2.  Contains  36'7  per  cent,  of  arsenic  acid,  to  56'4  of 
oxyd  of  copper.  Copper  Mica  is  remarkable  for  its  thin  foliated  or 
mica-like  structure.  The  color  is  emerald  or  grass-green.  H=2. 
Gr=2'55.  It  contains  21  per  cent,  of  arsenic  acid,  58  of  oxyd  of  cop- 
per, and  21  of  water.  From  Cornwall  and  Hungary.  Copper  Froth 
is  another  arsenate  of  a  pale  apple-green  and  verdigris  green  color.  It 

How  does  chrysocolla  differ  from  green  malachite  1  Where  is  it 
abundant  in  the  U.  States  ?  What  is  its  use  1 


COPPER    OTTES.  285 

kas  -a  perfect  cleavage.  It  contains  25  per  cent,  of  arsenic  acid,  43  9 
of  oxyd  of  copper,  17'5  of  water,  with  13  6  of  carbonate  of  lime.  From 
Hungary,  Siberia,  the  Tyr«L,  and  Derbyshire.  Condvrrite  has  a  brown- 
ish-black «r  blue  color.  From  Cornwall.  These  different  arsenates  of 
copper  give  an  aUicaceous  odor  w-hen  heated  on  charcoal  before  the 
blowpipe. 

Phosphates  of  -Copper. — Pseudo-malachite  occurs  in  very  oblique 
crystals,  or  .massive  and  incrusting,  and  has  an  emerald  or  blackish- 
green  color-  H=4'5 — 5.  Gr=4-2.  Contains  68  per  cent,  of  oxyd 
of  copper.  From  near  Bonn,  on  the  Rhine,  and  ako  fi»m  Hungary. 
Libethenite  has  a  dark  or  olive-green  color,  and  occurs  in  prismatic 
crystals  and  massive.  H=4.  Gr=3  6 — 3'8.  Contains  64  per  cent, 
of  oxyd  of  copper.  From  Hungary  and  Cornwall.  Tkrombolitc  is  a 
green  phospate  occurring  .massive  in  Hungary.  Contains  39  percent, 
of  oxyd  of  copper.  These  phosphates  give  no  fumes  before  the  blow- 
pipe ;  and  have  the  reaction  of  phosphoric  acid. 

Chlorid  of  Copper. — Atacamite.  Color  green  to  blackish-green, 
Luster  adamantine  to  vitreous.  Streak  apple-gpeen.  Translucent  te 
«ubtranslucenL  Occurs  tn  rig  lit  rhombic  prisms  and  rectangular  octa- 
hedrons, ako  .massive.  Consists  of  oxyd  of  copper  76'6,  muriatic  acid 
iO-6,  water  12-8.  -Gives  off  fumes  of  rmariatic  acid  before  the  blowpipe 
and  leaves  a  globule  of  -copper.  Fcom  the  Atacama  desert,  between 
Chili  and  Peru,  and  elsewhere  in  Chili  ;  also  from  Vesuvius  and  Sax- 
ony. It  is  ground  up  in  Chili,  and  sold  as  a  powder  for  letters  under 
the  name  of  arsenlllo. 

A  Sulphato-chlorid  of  Copper  hasibeen  observed  in  Cornwall,  in  olue 
acicular  crystals,  apparently  hexagonal. 

Beaumontite  of  C.  T.  Jackson,  is  a-  hydrous  c  Ferrate-silicate  of  cop- 
per, containing  15*8  per  cent,  of  crenic  acid.  It  is  bluish-green  to 
greenish-white,  and  pulverulent  when  dry.  From  Chessy,  France. 

Vanadate  of  copper.  Massive  and  foliated,  or  pulverulent ;  folia 
citron-yeHow,  pearly.  From  the  Ural, 

Buratite.  A  kydrous  carbonate  of  copper,  zinc,  and  lime,  occurring 
in  bluish  radiating  needles.  Gr=3  2.  From  Chessy,  France  ;  the  Al- 
tai mountains  ;  and  Tuscany. 

Velvet  Copper  Ore.  In  velvety  druses  or  coatings,  consisting  of 
fihort  fine  fibrous  crystaliizatioa.  Color  fine  smalt  blue. 

GENERAL  REMARKS  ON  COPPER  AND  ITS  ORES. 

The  metal  copper  has  been  .known  since  the  earliest  periods.  It  in 
obtained  for  tke  arts  mostly  from  pyriloua  copper,  the  gray  stdprrurets, 
and  the  carbonate  ;  also  to  some  ^extent  from  the  black  oxyd,  and  from 
solutions  of  the  sulphate,  (page  28L) 

Assay  of  Ores.  For  tie  assay  of  copper  ores  by  the  dry  way,  tk^ 
following  is  a  common  method.  A  portion  of  the  prepared  ore,  roasted 
in  a  closed  tube,  will  -show  by  the  garlic  or  sulphurous  smell  of  the 
fomes,  and  by  die  depositions  on  the  t*be,  whether  arsenic,  sulphur,  or 
both,  be  the  mineraliaers-  If  this  last  is  the  case,  which  often  happens, 
100  or  1000  grains  of  the  ore  are  to  be  mixed  with  one  half  of  its 
weight  of  sawdust,  then  imbued  witk  oil,  amd  heated  moderately  in  a 

VVLat  is  the  mode  of  assaying  copper  ores  in  ithe  dry  way  2 


METALS, 

crucible,  till  all  the  arsenical  fumes  are  dissipated.  The  residuum,,  be- 
ing  cooled  and  triturated,  is  to  be  exposed  in  a  shallow  earthen  dish, 
made  of  refractory  material,  to  a  slow  roasting  heat,  and  stirred  till  the 
sulphur  and  charcoal  are  burned  away  ;  what  remains  being  ground  and 
mixed  with  half  its  weight  of  calcined  boraa,  or  carbonate  of  soda,  one- 
twelfth  its  weight  of  lamp  black,  (finely  pulverized  charcoal  will  an- 
swer,) and  next,  made  into  a  dough  with  a  few  drops  of  oil,  is  then  to 
be  pressed  down  into  a  crucible,  which  is  to  be  covered  with  a  luted; 
lid,  and  subjected  in  a  powerful  air-furnace,  first  to  a  dull  red  heat,  then 
to  vivid  ignition  for  -seven  to»!wenty  minutes.  On  cooling  and  breaking 
the  crucible,  a  button  of  metallic  copper  will  be  obtained,  which  may 
be  refined  by  melting  again  with  borax  in  an  open  crucible.  Its  color 
and  malleability  indicate  pretty  well  the  quality,  as  does  its  weight  the 
relative  value,  of  the  ore.  It  may  be  eupeiled  with  lead  to  ascertain 
if  it  contain  silver  or  gold  ;  or  it  may  be  treated  for  the  same  purpose 
with  nitric  acid. 

If  the  blowpipe  trial  show  no  arsenic,  the  first  calcination  may  be 
omitted. ;  and  if  neither  sulphur  nor  arsenic  are  present,  a  portion  of  the- 
pulverized  ore  should  be  dried  and  treated  directly  with  borax,  lamp- 
black, and  oil. 

The  ores  of  copper,  (the  sulphuret  as  well  as  the  oxyds,  carbonates, 
&c.)  may  be  reduced  in  the  wet  way,  by  solution  in  strong  nitric  acid. 
The  solution,  if  made  from  the  sulphuret,.  will  contain  sulphuric  acid 
and  free  sulphur,  as  well  as  all  the  bases,  (iron,  nickel,  cobalt,  lead,  sil- 
ver, &c.)  which  may  have  been  present  in  the  original  ore.  If  silver 
is  present  it  will  be  found  as  a  heavy  white  curdy  precipitate,  at  the 
bottom,  if  the  nitric  acid  employed  contained  any  hydrochloric  acid  ; 
and  if  the  addition  of  this  acid  to  the  solution  occasions  no  such  pre- 
cipitate, no  silver  is  present.  If  the  solution  is  free  from  lead,  anti- 
mony,, arsenic,. and  oiher  metals  precipitable  by  sulphureted  hydrogen,. 
the  copper  may  be  thrown  down  as  sulphuret  by  means- of  a  current  of 
this  gas,  the  black  precipitate,  collected  on  a  filter  washed  with  water,, 
and  redissolved  in  aqua  regia,  largely  diluted,  and  finally  precipitated  by 
caustic,  potash,  which  throws  down  the  black  oxyd  of  copper.  This: 
dried  and  weighed  will  yield  the  true  value  of  the  are  in  metallic  cop- 
per. If  only  iron  and  capper  are  present,  (which  may  be  previously  de- 
termined by  the  blowpipe,)  they  may  be  separated  tiewn  their  solutions 
in  nitric  acid  by  ammonia,  which  throws  down  the  iron  as  hydrated 
peroxyd,  bat  redissolves  the  copper  precipitated  by  the  first  additions  of 
ammonia.  The  determination  of  the  weight  of  the  iron  may  then  give 
the  amount  of  copper  by  the  difference  of  weight,  or  the  copper  may 
again  be  thrown  down  by  potash  as  before  directed. 

Reduction  of  Ores.  Copper  ores  are  seduced  in  England  in  a  rever- 
feeratory  furnace,  and  the  process  consists  in  alternate  calcinations  and 
fusions.  The  volatile  ingredients  are  carried  off  by  the  caic  naik-ns> 
and  any  metals  in  combination  with  the  copper  are  oxydized.  The 
fusions  serve  to  get  lid  of  the  various  impurities,  and  finally  bring  out 
the  pure  metal. 

The  calcinations  ar  roasting.;  are  performed  either  in  a  furnace,-  OF 
by  making  piles  in  the  open  air.  In  this  latter  mode,,  which  is  in  use 

What  is  the  mode  of  assaying  copper  ores  in,  the  wet  way  1  IIov* 
are  copper  ores  reduced  ?  Describe  the  process  of  calcination  1 


COPPER    ORES.  287 

on  lire  continent  of  Europe,  the  ore,  after  being  pounded  and  assorted, 
is  piled  np  in  high  pyramidal  mounds,  which  mounds  are  covered  with 
mortar,  sod,  &c.,  and  have  a  chimney  at  the  center.  Hemispherical 
cavities  are  dug  on  the  upper  surface  for  the  purpose  of  receiving  the 
sulphur  during  the  roasting,  which  arrives  liquified  at  the  surface.  This 
process  lasts  about  six  months.  In  England,  at  Swansea,  where  the 
ores  are  carried  for  reduction,  the  calcinations  are  performed  more  rap- 
Idly  in  a  reverberatory  furnace  ;  and  this  is  especially  necessary  when 
the  ores  do  not  contain  a  sufficient  proportion  of  iron  pyrites  to  famish, 
(enough  sulphur  to  sastain  the  combustion.  After  calcination,  the  ore  is 
black  and  powdery.  In  the  Swansea  establishments,  the  calcined  ore 
is  introduced  into  the  furnace,  (a  reverberatory  smaller  than  that  used 
for  calcination,)  and  is  spread  over  the  bottom,  1  cwt.  at  a  time.  The 
heat  is  raised-,  and  the  furnace  closed.  When  fusion  has  taken  place, 
the  liquid  mass  is  well  rabbled  or  stirred,  so  as  to  allow  of  the  complete 
separation  of  the  slairs  from  the  metal ;  afterwards  the  slags  are  skimmed 
off.  Then  a  second  charge  is  added,  and  after  a  similar  process,  a 
third  charge,  if  the  furnace  is  deep  enough  to  receive  it  without  the 
metal's  flowing  from  the  door.  After  the  last  charge  is  reduced  also, 
the  tap-hole  is  opened,  and  the  metal  flows  out  into  water,  where  it  is 
granulated.  The  slags  if  not  free  from  metal  are  again  returned  to  the 
furnace,  when  other  charges  are  put  in.  This  granulated  metal  is 
usually  about  one-third  copper  ;  it  contains  sulphur,  copper,  and  iron. 

This  coarse  metal  is  next  calcined,  just  as  the  ore  was  first  calcined  ; 
by  which  the  iron  is  oxydized.  The  charge  remains  in  the  furnace  24 
hour;,  and  is  repeatedly  stirred  and  turned. 

It  is  then  transferred  to  the  furnace  for  melting,  and  there  melted 
along  with  some  slags  from  the  previous  fusion.  The  sulphur  reduces 
any  oxyd  and  the  whole  fuses  down.  The  slags  are  skimmed  off  and 
the  furnace  tapped  :  the  metal  is  again  drawn  off  into  water.  In  this 
state  it  contains  about  60  per  cent,  of  copper,  and  it  is  called  fine 
metal.  The  fine  metal  is  then  calcined  like  the  coarse  metal ;  and  next 
it  is  melted  as  before.  It  results  in  a  coarse  copper  containing  80  to  90 
per  cent,  of  pure  metal. 

The  coarse  copper  is  then  roasted  in  the  melting  furnace  ;  the  air 
drawing  in  large  quantities  over  the  copper  in  incipient  fusion,  oxydizes 
the  iron  and  the  volatile  substances  are  driven  off.  The  metal  is  fused 
toward  the  end  of  the  operation,  which  is  continued  from  12  to  24 
hours,  and  is  then  tapped  into  sand  beds.  The  pigs  formed  are  cov- 
ered with  black  blisters  and  they  are  cellular  within.  The  copper  is 
then  remelted  in  a  melting  furnace  ;  it  is  heated  slowly  to  allow  of  any 
farther  oxydizing  that  may  be  necessary.  The  slag  is  removed  and  the 
metal  is  examined  from  time  to  time,  by  taking  out  some  of  it,  and 
when  it  is  in  the  right  condition,  it  is  next  subjected  to  the  process  of 
toughening.  It  is  now  brittle,  of  a  deep  red  color  inclining  to  purple, 
with  an  open  grain  and  a  crystalline  structure  ;  the  copper  in  this  state 
is  what  is  termed  dry.  The  surface  of  the  melted  metal  is  first  cov- 
ered with  charcoal ;  a  pole,  commonly  of  birch,  is  held  in  the  liquid 
matter,  causing  considerable  ebullition  ;  and  this  poling  is  continued, 
with  occasional  additions  of  charcoal,  till  it  is  found  in  the  assays  taken 


What  are  the  several  steps  in  reduction  ? 


288  METALS, 

out  that  the  crystalline  grain  has  disappeared,  and  the  copper  when  en? 
through  has  a  silky  polished  appearance,  and  the  color  is  light  red, 
It  is  then  ladeled  out  into  moulds,  usually  12  inches  in  width  by  18  long, 
Lead  is  sometimes  added"  in  the  purification,  to  aid  by  its  own  oxyda- 
titon  in  the  oxydation  of  the  iron  present. 

The  process  of  melting  copper  on  the  continent  is  done  hy  blast  fur- 
naces instead  of  the  reverberatory,  and  they  are  sakf  to  be  more  eco- 
nomical in  fuel,  and  produce  a  less  waste  of  copper  in  the  slags.  This? 
mode  is  used  at  the  works  at  Boston,  while  the  Swansea  mode  hag 
been  adopted  at  the  Baltimore  furnaces,  Maryland,  At  the  Ha'ford 
works,  South  Wales,  a  furnace  of  three  tiers  of  hearths  has  been  intro- 
duced, which  answers  the  double  purpose  of  calcination  and  fusion  afc 
the  same  time. 

Galvanism  has  been  turned  to  account  in  the  reduction1  of  copper 
ores.  The  ore  is  converted  inta  a  sulphate  by  roasting  with  the  free 
access  of  the  atmosphere.  From  this  sulphate  the  copper  is  deposited 
in  a  pure  state  by  galvanic  decomposition.  See  on  this  subject  Ameri- 
can Journal  of  Science,  ii  ser,,  volume  iv,  p.  278,  or  Franklin  Journal, 
volume  xi,  p.  128. 

Copper  Mines.  The  principal  mrrres  of  copper  in  the  world  are  those 
of  Cornwall  and  Devon,  England  ;  of  the  island  of  Cuba  ;  of  Copiapo, 
and  other  places  in  Chili ;  Chessy,  near  Lyons,  in  FiiJne'e  ;  ifl  the 
Erzgebirge,  Saxony ;  at  Eisleben  and  Sangerhausen,  in  Prussia  ;  at 
Goslar,  in  the  Lower  Hartz  ;.  at  Scheminitz,  Kremnitz,  Kapnik,  and 
the  Bannat,  in  Hungary  ;  at  Fahkn,  in  Sweden  ;  at  Turinsk  and  Nisch- 
ni-Tagilsk,  and  other  places  in  the  Urals  ;  also  in  China  and  Japan, 
Lately  extensive  mines  have  been  opened  in  Southern  Australia. 

In  the  United  States,  considerable,  quantities  have  been  raised  from 
the  mines  of  New  Jersey,  and  those  of  Simsbury,  Conn.  At  Bristol, 
Conn.,  is  a  fine  vein  of  vitreous  copper,  now  under  exploration.  Straf- 
ford,  Vermont,  affords  some  tons  of  pyritous  copper  at  the  present  time 
for  the  Boston  furnace. 

The  most  extensive  deposits  are  those  of  Northern  Michigan  and 
Wisconsin.  The  Michigan  mines  are  vertical  veins  mostly  in  the  trap 
fock  which  intersects  a  red  sandstone,  probably  identical  in  age  with 
the  red  sandstone  of  Connecticut  and  New  Jersey.  The  first  discov- 
eries of  copper  ore  in  this  place  were  made  at  Copper  harbor,  where  the 
chrysocolla  and  carbonate  occur.  Near  Fort  Wilkins  the  black  oxyd 
was  afterwards  found  in  a  large  deposit,  and  40,000  pounds  of  this  ore 
were  shipped  to  Boston.  On  farther  exploration  in  the  trap,  the  Cliff 
mine,  25  miles  to  the  westward,  was  laid  open,  where  the  largest  masses 
of  native  copper  have  been  found,  and  which  still  proves  to  be  highly 
productive.  Other  veins  have  since  been  opened  in  various  parts  of  the 
region,  at  Eagle  harbor,  Eagle  river,  Grand  Marais,  Lac  La  Belle, 
Agate  Harbor,  Torch  Lake,  on  the  Ontonagon,  in  the  Porcupine  moun- 
tains, and  elsewhere.  At  Mineral  Point,  Wisconsin,  a  blue  siliceous 
carbonate  is  abundant.  Other  mines  are  opened  in  Missouri.  The 
country  north  of  Lakes  Superior  and  Huron,  also  abound  in  copper  ores. 

What  is  the  process  of  reduction  on  the  continent  of  Europe  ?  Where 
are  the  principal  foreign  mines  of  copper  ?  Where  is  copper  found  in 
the  United  States? 


COPPER    ORES.  289 

In  the  Lake  Superior  Region,  Michigan,  the  amount  of  ores  and 
metals  raised  and  shipped  during  the  year  ending  September  30,  1847, 
is  stated  by  the  Mineral  Agent  as  follows  : 

Ores  and  metaL  Am't  shipped. 

Lake  Superior  Company,  1,114,841  Ibs.  31,441 

Eagle  Harbor  Company,  321,000  61  154 

Copper  Falls  Company,  317,050  15^26*3 

Pittsburg  and  Boston  Company,  7,283,340  1,497,481 

North  West  Company,  190,000  7,264 

Lac  La  Belle  Company,  200,000  1,328 

Suffolk  Company,  300,000  383 

Algonquin  Company,  120,000  11,135 

Bohemia  Company,  80,000  4,049 

All  others  making  reports,  1,327,969  40,206 

10,214,200  1,693,805 

The  amount  of  copper  produced  by  different  mining  countries  in  Eu- 
rope, is  as  follows: — 


Great  Britain,  360,000  cwt.* 

Russia,  50,000    " 

Austria,  50,000    " 


Denmark,  8,500  cwt. 

Prussia,  6,400    * 

France,  1,000    " 

Spain,  300    " 


Germany,  25,000 

Sweden  and  Norway,  30,000 

Large  quantities  of  ore  are  now  imported  from  Southern  Australia 
into  England  ;  and  Chili  and  Cuba  have  long  furnished  copper  ores  to 
England,  and  to  some  extent,  to  this  country.  What  will  be  ultimately 
the  proceeds  of  the  copper  region  of  Lake  Superior,  cannot  now  be  fully 
determined.  But  there  is  every  prospect  that  the  country  will  prove 
boundless  in  its  resources, 

Uses.  The  metal  copper  was  known  in  the  earliest  periods  and  was 
used  mostly  alloyed  with  tin,  forming  bronze.  The  mines  of  Nubia 
and  Ethiopia  are  believed  to  have  produced  a  great  part  of  the  copper 
of  the  early  Egyptians.  Eubaea  and  Cyprus  are  also  mentioned  as  af- 
fording this  metal  to  the  Greeks.  It  was  employed  for  cutting  instru- 
ments and  weapons,  as  well  as  for  utensils ;  and  bronze  chisels  are  at 
this  day  found  at  the  Egyptian  stone-quarries,  that  were  once  employed 
in  quarrying.  This  bronze,  (chalkos  of  the  Greeks,  and  as  of  the  Ro- 
mans,) consisted  of  about  5  parts  of  copper  to  1  of  tin,  a  proportion 
which  produces  an  alloy  of  maximum  hardness.  Nearly  the  same  ma- 
terial was  used  in  early  times  over  Europe  ;  and  weapons  and  tools 
have  been  found  consisting  of  copper,  edged  with  iron,  indicating  the 
scarcity  of  the  latter  metal.  Similar  weapons  have  also  been  found  in 
Britain  ;  yet  it  is  certain  that  iron  and  steel  were  well  known  to  the 
Romans  and  later  Greeks,  and  to  some  extent  used  for  warlike  weapons 
and  cutlery. 

Copper  at  the  present  day  is  very  various  in  its  applications  in  the 

1     How  did  the  ancients  use  copper?     What  is  the  proportion  of  alloy 
in  the  ancient  bronze  ? 

*  5-6  of  the  whole  from  Cornwall. 
25 


290  METALS'. 

arts.  It  is  largely  employed  for  utensils,  for  the  sheathing  of  ships,  and 
for  coinage.  Alloyed  with  zinc  it  const' tutes  brass,  and  with  tin  if 
forms  bell-metal  as  well  as  bronze. 

The  best  brass  contains  2  parts  of  copper  to  1  of  zinc  ;  the  propor- 
tion of  4  of  copper  to  1  of  zinc,  makes  a  good  brass.  Pinchbeck 
contains  5  of  copper  to  1  of  zinc  ;  and  tombac  and  Dutch  gold,  are 
other  allied  compounds  Bath  metal  consists  of  9  of  zinc  to  32  of 
brass.  A  whitish  metal"  nsed  by  the  button-makers  of  Birmingham,  and 
called  platina,  is  made  of  5  pounds  of  zinc  to  8  of  Brass. 

fironze  is  an  alloy  of  copper  with  7  to  10  per  cent,  of  tin.  This  is 
the  material  used  for  cannon.  With  8  per  cent,  of  tin,  it  is  the  bronze 
for  medals.  With  20  of  tin,  the  material  for  cymbals.  With  30  to  33 
parts  of  tin,  it  forms  speculum  metal,  of  which  the  mirrors  for  optical 
instruments  are  made.  Lord  Rosse  used  for  fhe  speculum  of  his  great 
telescope,  126  parts  of  copper  to  57^  parts  of  tin. 

The  brothers  Keller,  celebrated  for  their  statue  castings,  used  a  metal 
consisting  of  91 -4  per  cent,  of  copper,  5'53  of  zinc,  1'7  of  tin,  and  T37 
of  lead.  An  equestrian  statue  of  Louis  XIV,  21  feet  high,  and  weigh- 
ing 53,263  French  pounds,  was  cast  by  them  in  1G99,  at  a  single  jet, 

Sell-metal  is  made  of  copper  with  a  third  to  a  fifth  as  much  tin  by 
weight,  the  proportion  of  tin  varying  according  to  the  size  of  the  bell 
and  sound  required.  The  Chinese  gong  contains  80  parts  of  copper  tor 
20  or  25  of  tin  ;  to  give  it  its  full  sonorousness,  it  must  be  heated  and 
suddenly  cooled  in  cold  water. 

Sheet  copper  is  made  by  heating  the  copper  in  a  furnace  and  rolling 
it  between  iron  rollers.  Copper  is  also  worked  by  forging  and  casting, 
In  casting,  it  will  not  bear  over  a  red  heat  without  burning. 


15.     TITANIUM. 


Titanium  occurs  in  nature  combined  with  oxygen,  forming 
titanic  acid  or  oxyd,  and  also  in  combinations  with  different 
bases.  It  has  rarely  been  met  with  native. 

The  ores  are  infusible  alone  before  the  blowpipe,  or  nearly 
so.  Their  specific  gravity  is  between  3*0  and  4*5.  With 
salt  of  phosphorus,  in  the  inner  flame  on  charcoal,  a  globule 
is  obtained  with  some  difficulty,  whi<  .h  is  violet  blue  when 
cold. 

Native  titanium  occurs  in  cubes,  of  a  copper-red  color,  in 
Cornwall.  It  is  a  frequent  product  of  furnaces,  having  been 
often  met  with  in  slags. 


What  is  the  composition  of  brass  ?  of  pinchbeck  ?  of  bronze  for  can- 
non and  medals  ?  bronze  for  statuary  ?  speculum  metal  ?  How  does 
titanium  occur  ?  What  is  said  of  its  ores  ? 


r»Rr.s  OF  TITANIUM.  291 


RUT1LE. 

Dimelric.  In  prisma  of  eight,  twelve,  or  more  sides, 
with  pyramidal  terminations,  and  often  bent 
as  in  the  figure,;  a  :  a  =  117°2'.  Crystals 
often  acicular,  and  penetrating  quartz.  Some- 
times massive.  Cleavage  lateral,  somewhat 
distinct. 

Color  reddish-brown  to  nearly  red;  streak  very  pale- 
brown.  Luster  submetallic-adamantine.  Transparent  to 
opaque.  Brittle.  H=6 — 6  '5.  Gr=4'15 — 4'2§. 

Composition :  titanium  6 1 ,  oxygon  39.  Sometimes  contains 
iron,  and  has  nearly  a  black  color ;  this  variety  is  called 
rrigrine.  Unaltered  alone  before  the  blowpipe.  Forms  a 
•hyacinth-red  bead  with  borax. 

Dif.  The  peculiar  subadamantine  luster  of  Tutile,  and 
brownish-red  color,  much  lighter  red  in  splinters,  are  striking 
characters.  It  differs  from  tourmaline,  Idocrase,  and  augite, 
!  by  being  unaltered  when  heated  alone  "before  the  blowpipe ; 
and  trom  tin  ore,  in  Rot  affording  tin  with  soda  ;  from  sphene 
iii  its  crystals. 

Obs.     Occurs  imbedded  in  granate,  gneiss,  «iica  slate, 

syenite,  and  in  granular  limestone.     Sometimes  associated 

i  with  specular  iron,  as  at  the  Orisons.     Yrieix  in  France, 

!  Castile,  Brazil,  and  Arendal  in  Norway,  are  some  of  the 

i  foreign  localities. 

In  the  United  States,  H  occurs  in  crystals  in  Maine,  aft 

I  Warren;  in  New  Hampshire,  at  Lyme  and  Hanover;  in 

|  Massachusetts,  at  Barre,  Windsor,  Shelburne,  Leyden,  Con- 

!  *vay  ;  in  Connecticut,  at  Monroe  and  Huntington  ;  in  New 

York,  near  Edenville,  Warwick,  Amity,  at  Kingsbridge,  and 

i  in  Essex  county  at  Gouverneur  ;  in  the  District  of  Columbia, 

at  Georgetown ;  in  North  Carolina,  in  Buncombe  county; 

:  an  the  gold  district  of  Georgia. 

Uses.     The  specimens  of  limpid -quartz,  penetrated  by  long 

acicular  crystals,  are  o&en  very  elegant  when  polished.     A 

;  remarkable  specimen   of  this  kind  was  obtained  at  Han- 

!  -over,  N.  H.,  and  less  handsome  ones  are  not  uncommon. 

Polished  stones  of  this  kind  are  called  fleches  <T  amour  (love's 

'  arrows)  by  the  French. 

Describe  rutHe.  Of  what  does  it  consist?  How  is  it  distinguished 
fcom  ether  minerals?  WJi  at  are  its -uses  .2 


292 


METALS. 


This  ore  is  employed  in  painting  on  porcelain,  and  qorte 
largely  for  giving  the  requisite  shade  of  color  and  enamel 
appearance  to  artificial  teeth. 

Anatase.  Brookite.  These  species  have  the  same  composition  as 
rutile.  Anatase  occurs  in  slender  nearly  transparent  octahedrons,  of  a 
brown  color.  A  :  A=97°  56'.  H=5'5— 6.  Gr=3'8— 3>9.  From 
Dauphiny,  the  Tyrol,  and  Brazil.  Said  to  accompany  native  titanium 
in  slags  from  the  iron  furnaces  of  Orange  county,,  N.  Y. 

Brookite  is  met  with  in  thin  hair-brown  crystals,  attached:  by  one 
edge.  H=5~5 — 6.  The  crystals  are  secondaries  to  a  rhombic  prism. 
From  Dauphiny,  and  Snowdon  in  Wales.  Said  to  occur  at  the  Phenix- 
ville  tunnel  on  the  Reading  railroad,  Fa.  See  Arkansiter  p.  209, 

SPHENE. 

Monoclinate.     In  very  oblique  rhombic  prisms  ;  the  lat- 
eral faces  having  angles  either  of  76°  1',  1I3J  27'  (r  :  r) 
1  3 


136°  &'  (n  :  n),  or  133°  48*.  The  crystals  are  usually  thin 
with  sharp  edges.  Cleavage  in  one  direction  sometimes 
perfect.  Occasionally  massive. 

Color  grayish-brown,  gray,  brown  or  black  ;  sometimes 
yellow  or  green  ;  streak  uncolored.  Luster  adamantine  to 
resinous.  Transparent  to  opaque.  H  =  5  —  5.5.  Gr  = 


Composition:  silica  34-2,  titanfc  acid  44*7,  lime  21  •!. 
Before  the  blowpipe,  the  yellow  varieties  are  unaltered  in 
color,  and  others  become  yellow  ;  on  charcoal,  they  fuse  on 
the  edges  with  a  slight  intumescence  to  a  dark  glass. 

The  dark  varieties  of  this  species  were  formerly  called 
titanite  and  menaccanite,  and  the  lighter  spJiene.  The  name 
sphene  alludes  to  the  wedge-shaped  crystals,  and  is  from  the 
Greek  sphen,  a  wedge. 

What  is  said  of  the  crystals  of  sphene  I  What  are  the  color,  luster, 
and  hardness  ?  the  composition  1 


ORES  OF   TITANIUM,  293 

Dif.  The  crystals,  in  general,  by  their  thin  wedge  shape, 
readiiy  distinguish  this  species  when  crystallized  ;  but  some 
crystals  are  very  complex.  From  garnet,  tourmaline,  and 
idocrase,  this  species  is  distinguished  by  its  infusibility  before 
the  blowpipe. 

Obs.  Sphene  occurs  mostly  in  disseminated  crystals  in 
granite,  gneiss,  mica  slate,  syenite,  or  granular  limestone.  It 
is  usually  associated  with  pyroxene  ai*d  scapolite,  and  often 
with  graphite.  It  has  been  found  in  volcanic  rocks.  The 
crystals  are  commonly  J  to  £  an  inch  long  ;  but  are  some* 
times  1  to  2  inches. 

Foreign  localities  are  Arendal  in  Norway  ;  at  St.  Gothard 
and  Mount  Blanc }  in  Argyleshire  and  Galloway  in  Great 
Britain. 

In  the  United  States,  it  is  met  with  in  good  crystals  in 
New  York,  at  Rogers'  Rock  on  Lake  George,  with  graphite 
and  pyroxene,  at  Gouverneur,  near  Natural  Bridge  in  Lewis 
county,  (the  variety  called  lederite,)  in  Orange  county  in 
Monroe,  Edenville,  Warwick,  and  Amity,  near  Peekskill  in 
Westchester  county,  and  near  West  Farms.  In  Massachu- 
sets,  at  Lee,  Bolton,  and  Pelham.  In  Connecticut,  at  Trum- 
bull.  In  Maine,  at  Thomaston.  In  New  Jersey,  at  Frank- 
lin.  In  Pennsylvania,  near  Attleboro',  Bucks  county.  In 
Delaware,  at  Dixon's  quarry,  7  miles  from  Wilmington.  In 
Maryland,  25  miles  from  Baltimore,  on  the  Gunpowder. 

GreenovUe  is  a  sphene  containing  manganese, 

Perovskite.  This  is  a  titanate  of  lime.  It  occurs  in  minute  modified 
cubes,  grayish  to  iron-black  in  color.  Gr=4'0l7.  H=5'5.  From  the 
Urals. 

Pyrrhite.  In  minute  regular  octahedrons,  of  a  yellowish  color. 
Transparent ;  vitreous.  H=6.  From  near  Mursinsk,  Siberia ;  also 
from  the  Western  Islands,  as  first  detected  by  Mr.  J.  E.  Teschemacher 
of  Boston.  Supposed  to  contain  titanic  acid. 

Keilhauite,oryttro~titanite.  Massive;  cleavable.  Brownish-black, 
with  a  grayish-brown  powder.  Gr=3'69.  H=6  5.  Fuses  easily. 
Contains  silica  30'0,  titanic  acid  29'0,  yttria  9*6,  lime  18'9,  peroxyd  of 
iron  6'4,  alumina  6'1.  From  Arendal,  Norway. 

Warwickite.  It  occurs  in  prismatic  crystals,  of  a  brownish  to  an  iron- 
gray  color,  often  tarnished  bluish  or  copper-red.  Luster  metallic  pearly 
to  imperfectly  vitreous  or  resinous.  H=5 — 6.  Gr=3 — 3'3.  Infusible 
alone  before  the  blowpipe.  From  magnesian  limestone,  with  ilmenite 
and  spinel,  at  Amity,  Orange  county,  N.  Y. 


What  are  distinctive  characteristics  of  the  species  sphene?     In  what 
rocks  does  it  occur  ? 


294  MITTAL9, 

The  analysis  of  warwfckit'e-,  by  Prof.  Shepard,  made  ft  a  fluo-titanat* 
of  iron,  with  some  yttria.  It  has  since  been  examined  by  Mr.  T.  Sv 
Hunt,  who  found  it  to  contain  no  fluorine,  and  to  be  a  silicate  and  ti- 
tanate  of  iron,  magnesia,  and  alumina,  with  7  per  cent,  of  water.  Mr, 
Hunt  named  the  specks  examined  by  him  enceladite.  He  states  the 
hardness  as  between  3  and  4. 

Besides  the  ores  here  described,  titanium  is  an  essential 
constituent  also  of  ihnenite,  (titanic  iron)  ;  also  in  the  zir- 
conia  and  yttria  ores  <z$chynite,  cerstedite,  and  polymignite^ 
and  in  some  other  rare  species  j  sometimes  in  pyrochlore. 

The  metal  titanium  has  seldom  been  obtained  in  the  me- 
tallic state,  and  is  not  used  in  the  arts.  The  uses  of  the 
oxyd  have  been  mentioned. 

16.    TIN. 

Tin  has  been  reported  as  occurring  native.  There  are 
two  ores,  the  oxyd  and  a  sulphured  It  also  occurs  in  some 
ores  of  columbium.  The  specific  gravity  of  the  sulphuret  is 
between  4'3  and  4*4  ;  that  of  the  oxyd,  between  6-5  and  7*1. 
With  carbonate  of  soda  on  charcoal,  a  globule  of  tin  is  ob- 
tained. When  the  tin  is  in  minute  quantities  in  a  mineral, 
it  is  well  to  add  also  some  borax,  and  by  this  means,  especi- 
ally if  any  iron  present  be  first  removed,  or  if  it  be  only  in 
small  quantaties,  even  a  |  per  cent,  of  tin  may  be  detected. 

Native  tin  is  found  in  gray  metallic  grams  in  the  gold 
washings  of  the  Ural.  The  crystals  of  pure  tin  are  either 
tesseral  (cubic),  or  dimetric,  this  metal  being  dimorphous. 

TIN  PYRITES. — Sulplwret  of  Tin. 

In  cubes  and  massive.  Color  steel-gray  or  yellowish. 
Streak  black.  Brittle.  H=4.  Gr  =  4-3— 4-4. 

Composition  :  sulphur  25,  tin  34,  copper  36,  iron  2. 

Obs.  This  rare  ore  has  been  found  only  in  Cornwall, 
where  it  is  often  called  bell-metal  ore,  from  its  frequent 
bronze  appearance. 


How  does  tin  occur  in  the  mineral  kingdom  1  How  is  it  detected 
by  the  blowpipe?  What  is  the  appearance  and  composition  of  tin 
pyrites  ? 


TIX 


295 


TIN  ORE. — 'Oxyd  of  Tin. 

Dimetric.     In  modified  square  prisms  and  octahedrons  ; 

often  compound  :  e  :  e=121° 

35' ;  a  :  a  (over  the  summit) 

112°  01' ;    a  :  a  (over  a  ter- 
minal edge)  132°  53' ;  M  : 

e=133°  38' ;   M  :  e=135°. 

Cleavage     indistinct.      Also 

massive  or  in  grains. 
^^^^  Color  brown  or  black,  with 

a  high  adamantine  luster  when  in  crystals.  Streak  pale 
gray  to  brownish.  Nearly  transparent  to  opaque.  H  =6 — 
7.  Gr=6-5— 7-1. 

Composition  :  when  pure,  tin  78'62,  oxygen  21*38  ;  often 
contains  a  little  oxyd  of  iron,  and  sometimes  oxyd  of  colum- 
bium.  Before  the  blowpipe  alone,  infusible ;  with  soda, 
affords  a  globule  of  tin. 

Stream  tin  is  the  gravel-like  ore  found  in  debris  in  low 
grounds.  Wood  tin  occurs  in  botryoidal  and  reniform  shapes 
with  a  concentric  and  radiated  structure  ;  and  toad's-eye  tin 
is  the  same  on  a  small  scale. 

Dif.  Tin  ore  has  some  resemblance  to  a  dark  garnet, 
to  black  zinc  blende,  and  to  some  varieties  of  tourmaline.  It 
is  distinguished  by  its  infiisibility,  and  its  yielding  tin  before 
the  blowpipe  on  charcoal  with  soda.  It  differs  from  blende 
also  in  its  superior  hardness,  and  in  giving  no  fumes  on  char- 
coal before  the  blowpipe. 

Obs.  Tin  ore  occurs  in  veins  in  the  crystalline  rocks 
granite,  gneiss,  and  mica  slate,  associated  often  with  wolfram, 
copper  and  iron  pyrites,  topaz,  tourmaline,  mica  or  talc,  and 
albite.  Cornwall  is  one  of  its  most  productive  localities. 
It  is  also  worked  in  Saxony,  at  Altenberg,  Geyer,  Ehren- 
friedersdorf  and  Zinnwald  ;  in  Austria,  at  Schlackenwald  and 
other  places ;  in  Malacca,  Pegu,  China,  and  especially  the 
Island  of  Banca  in  the  East  Indies.  It  has  also  been  found 
in  Galicia,  Spain  ;  at  Dalecarlia  in  Sweden ;  in  Russia  ;  in 
Mexico,  Brazil,  and  Chili ;  in  the  United  States,  at  Chester- 
field and  Goshen,  Mass.,  in  some  of  the  Virginia  gold  mines, 

What  is  the  crystallization  of  tin  ore  ?  Mention  its  other  physical 
characters?  What  is  its  composition  and  blowpipe  reactions  ?  What 
is  stream  tin  ?  wood  tin,  and  toad's  eye  1  How  is  tin  ore  distinguished 
from  garnet,  blende,  and  tourmaline  ? 


296  METALS. 

and  in  Lyme  and  Jackson,  N.  H.  At  the  last  mentioned 
place,  where  this  ore  was  discovered  by  Dr.  C.  T.  Jackson, 
there  are  sufficient  indications  to  warrant  exploration. 

GENERAL  REMARKS  ON  TIN  AND  TIN  ORES. 

The  principal  tin  mines  now  worked,  are  those  of  Cornwall,  Banco 
and  Malacca,  Saxony,  and  Austria. 

The  Cornwall  mine's  are  supposed  to  have  been  worked  long  before 
the  Christian  era.  Herodotus,  450  years  before  Christ,  is  believed  to 
allude  to  the  tin  islands  of  Britain  under  the  cabalistic  name  cassiterides, 
derived  from  the  Greek  kassiteros,  signifying  tin.*  The  Phoenicians 
are  allowed  to  have  traded  with  Cornubia,  (as  Cornwall  was  called,  it 
is  supposed  from  the  horn  shape  of  this  western  extremity  of  England.) 
The  Greeks  residing  at  Marseilles  were  the  next  to  visit  Cornwall,  or 
the  isles  adjacent,  to  purchase  tin  ;  and  after  them  came  the  Romans, 
whose  merchants  were  long  foiled  in  their  attempts  to  discover  the  tin 
market  of  their  predecessors. 

Camden  says:  "  It  is  plain  that  the  ancient  Britons  dealt  in  tin  mines 
from  the  testimony  of  Diodorus  Siculus,  who  lived  in  the  reign  of  Augus- 
tus and  Timaus,  the  historian  in  Pliny,  who  tells  us  that  the  Britons 
fetched  tin  out  of  the  Isle  of  Icta,  (the  Isle  of  Wight,)  in  their  little 
wicker  boats  covered  with  leather.  The  import  of  the  passage  in 
Diodorus,  is  that  the  Britons  who  lived  in  those  parts  dug  tin  out  of  a 
rocky  sort  of  ground,  and  carried  it  in  carts  at  low  water  to  certain 
neighboring  islands  ;  and  that  from  thence  the  merchants  first  trans- 
ported it  to  Gaul,  and  afterwards  on  horseback  in  thirty  days  to  the 
springs  of  Eridanus,  or  the  city  of  Narbona,  as  to  a  common  mart. 
JEthicus  too,  another  ancient  writer,  intimates  the  same  thing,  and  adds 
that  he  had  himself  given  directions  to  the  workmen."  In  the  opinion 
of  the  learned  author  of  the  Britannica  here  quoted,  and  others  who  have 
followed  him,  the  Saxons  seem  not  to  have  meddled  with  the  mines,  or 
according  to  tradition,  to  have  employed  the  Saracens ;  for  the  inhabi- 
tants of  Cornwall  to  this  day  call  a  mine,  that  is  given  over  working 
Altai- Sarasin,  that  is,  the  leavings  of  the  Saracens.t 

The  Cornwall  veins,  or  lodes,  mostly  run  east  and  west,  with  a  dip — • 
hade,  in  the  provincial  dialect — varying  from  north  to  south  ;  yet  they  are 
very  irregular,  sometimes  crossing  each  other,  and  sometimes  a  prom- 
ising vein  abruptly  narrows  or  disappears  ;  or  again  they  spread  out  into 
a  kind  of  bed  or  floor.  The  veins  are  considered  worth  working  when 
but  three  inches  wide.  The  gangue  is  mostly  quartz,  with  some  chlo- 


Where  are  the  principal  tin  mines  1  What  is  said  of  the  Cornwall 
veins? 

*  This  term  and  the  stannum  of.  the  Romans,  or  plumbum  candidum, 
are  supposed  to  include  the  white  compounds  of  lead  and  other  metals ; 
and  it  has  even  been  doubted  whether  the  metal  tin  was  ordinarily 
included. 

t  Manuf.  in  Metals  ;  London,  1834,  iii,  2. 


TIX    ORES.  297 

rite.  Much  of  the  tin  is  also  obtained  from  loose  stones ;  (called  shodes,) 
and  courses  of  such  stones  or  tin  debris  are  called  streams,  whence  the 
name  stream  tin. 

The  ore  taken  from  the  mines  is  first  pounded  or  stamped  in  a  stamp- 
ing mill,  and  then  washed  by  running  water,  which  carries  off  to  a  great 
extent  the  lighter  impurities  and  leaves  the  heavy  ore  behind,  with  still 
some  of  the  gangue.  It  is  next  roasted  in  a  reverberatory  furnace,  to 
expel  any  arsenic  or  sulphur  derived  from  the  presence  of  other  ores,  and 
then  again  washed.  After  being  thus  purified  as  far  as  possible,  the  ore 
is  usually  mixed  with  pit-coal  and  a  little  lime,  and  strongly  heated  in 
either  a  reverberatory  furnace  or  what  is  called  a  blowing  furnace.  A 
state  of  fusion  is  kept  up  for  about  eight  hours.  The  metal  is  then 
drawn  off  into  iron  vessels.  As  it  contains  still  some  slag  or  earthy 
matters,  it  is  remelted  at  a  lower  temperature,  which  does  not  fuse  the 
impurities,  and  kept  agitated  for  a  while  by  wet  charcoal  or  carbonized 
\vcod  ;  it  is  then  skimmed  and  run  into  blocks,  weighing  from  275 
to  325  pounds  each.  The  tin  thus  made  from  the  ore  derived  from  the 
mines,  is  called  block  tin,  and  is  less  pure  than  that  from  the  stream  ore  ; 
the  latter  was  formerly  called  grain  tin,  though  now  this  is  a  general 
term  applied  to  the  purest  kinds  of  tin  in  commerce. 

In  an  assay  of  tin  ore,  after  pulverizing,  washing,  roasting,  and  weigh- 
ing, the  ore  should  be  mixed  with  lampblack  or  charcoal,  and  heated 
quickly  in  a  covered  crucible  to  a  white  heat.  On  removing  the  crucible 
from  the  fire,  a  button  of  tin  will  be  found  in  it.  If  the  ore  is  not  pure, 
carbonate  of  soda  or  borax  may  be  added  to  the  lampblack.  The  result 
is  good  if  the  tin  obtained  is  malleable  and  not  brittle.  The  tin  may  be 
farther  purified  by  fusing  it  in  a  ladle,  and  pouring  it  into  another  ves- 
sel whenever  the  cooling  has  hardened  the  alloys,  or  just  before  the  tin 
itself  begins  to  harden  ;  it  will  flow  out,  leaving  the  impurities  behind. 

The  best  tin  ores  afford  65  to  70  per  cent,  of  tin  in  the  large  way. 

The  annual  production  of  tin  in  different  countries,  is  as  follows : 

Great  Britain,       .         .         .  80,000  to  100,000  cwt. 

Banca  and  Malacca,     .         .  90,000 

Saxony,        ....  3,500 

Austria,        ....  380 

Sweden,       .....  750 

Tin  is  used  in  castings,  and  also  for  coating  other  metals,  especially 
iron  and  copper.  Copper  vessels  thus  coated  were  in  use  among  the 
Romans,  thongh  not  common.  Fliny  says  that  the  tinned  articles  could 
scarcely  be  distinguished  from  silver,  and  his  use  of  the  words  incoquere 
and  incoctilia,  seems  to  imply,  as  a  writer  states,  that  the  process  was 
the  same  as  for  the  iron  vares  of  the  present  day,  by  immersing  the 
vessels  in  melted  tin.  Tne  sheets  of  iron  for  tinning  are  cleaned  with 
acid,  heated,  and  then  cold-rolled  ;  again  subjected  to  dilute  acid,  and 
afterwards  scoured  with  sand  in  pure  water  :  then  two  or  three  hundred 


What  are  the  steps  in  the  process  of  reduction  ?  Describe  the  mode 
of  assaying  tin  ore.  What  is  the  yield  of  Great  Britain  in  tin  ?  What 
the  whole  amount  from  the  tin  mines  of  the  world  1  How  is  iron 
tinned  1 


£98  METALS, 

sheets  in  a  vertical  position  are  immersed,  first  in  a  vat  of  grease,  and 
then  in  a  cast  iron  bath  containing  about  5  cvvt.  of  melted  tin  ;  they 
remain  in  the  tin  for  an  hour  and  a  half,  and  are  then  taken  out.  As 
there  is  now  two  or  three  times  too  much  tin  on  the  plates,  they  are 
made  to  undergo  a  process  called  washing,  in  a  vessel  of  melted  grain 
tin,  by  which  the  excess  of  tin  is  removed  ;  after  which  they  are  cleaned 
and  rubbed  in  bins  of  dry  bran  until  they  receive  the  characteristic  sil- 
ver polish. 

When  tin  plate  slightly  heated  is  sponged  over  quickly  by  an  acid, 
(nitro-rnuriatic,)  the  crystalline  character  of  the  tin  is  brought  out,  and 
the  ware  so  treated  is  called  moire  metallique.  The  plate  before  sub- 
jecting it  to  the  acid  should  be  well  washed  with  alkali ;  and  after  the 
action  it  shoald  be  immediately  washed  in  clean  water  and  dried. 

Tin  is  also  used  extensively  as  tinfoil,  the  sheets  of  which  are  about 
1000th  of  an  inch  thick ;  also  with  quicksilver  it  is  used  to  cover  glass 
in  the  manufacture  of  mirrors.  It  is  alloyed  with  copper  in  various  pro- 
portions, constituting  thus  7  to  10  per  cent,  of  bronze  ;  20  per  cent,  of 
the  ancient  bronze  for  weapons ;  20  per  cent,  of  the  metal  for  cymbals 
and  the  Chinese  gong  ;  20  to  30  per  cent,  of  bell  metal ;  and  30  to  40 
per  cent,  of  speculum  metal,  (see  page  290,) 

The  oxyd  of  tin,  as  obtained  by  chemical  processes,  is  employed  on 
account  of  its  hardness  for  forming  a  paste  for  sharpening  fine  cutting 
instruments.  The  chlorid  of  tin  is  an  important  agent  in  the  precipi- 
tation of  many  colors  as  lakes,  and  in  fixing  and  changing  colors  in 
dyeing  and  calico  printing.  The  bisulphuret  of  tin  has  a  golden  luster, 
and  was  termed  aurum  musivum,  or  mosaic  gold?  by  the  alchemists. 
It  is  much  used  for  ornamental  painting,  for  paper  hangings  and  other 
purposes,  under  the  name  of  bronze  powder. 

Pins  are  tinned  by  boiling  them  for  a  few  minutes  in  a  solution  of  1 
part  of  crearn  tartar,  2  of  alum,  2  of  common  salt,  in  10  or  12  of  waler, 
to  which  some  tin  filings  or  finely  granulated  tin  are  added. 

Tin  medals  or  castings,  are  bronzed  by  being  washed  over  with  a 
solution  of  1  part  of  protosulphate  of  iron,  I  of  sulphate  of  copper,  in  20 
of  water;  this  gives  a  gray  tint ;  they  are  then  brushed  over  with  a 
solution  of  4  parts  of  verdigris  in  11  of  distilled  vinegar,  and  then 
polished  with  a  soft  brush  and  colcothar. 

17.     MOLYBDENUM. 

Molybdenum  occurs  in  nature  as  a  sulphuret,  and  sparingly 
as  an  oxyd.  Also  as  molybdic  acid,  in  molybdate  of  lead. 

1.     MOLYBDENITE. — Sulphuret  of  Molybdenum. 

In  hexagonal  crystals,  plates,  or  masses,  thin  foliated  like 
graphite,  and  resembling  that  mineral.  Color  pure  lead- 
gray  ;  streak  the  same,  slightly  greenish.  Thin  laminae 
very  flexible  ;  not  elastic.  H=l — 1-5.  Gr=4*5 — 4'75. 

In  what  other  way  is  tin  used  ?  What  alloys  are  made  with  it  ? 
What  are  the  characters  of  molybdenite  I 


JlOLYBDETfUM— TUXGSTEN.  299 

Composition  :  molybdenum  59'8,  sulphur  40*2.  Infusible 
before  the  blowpipe,  but  when  heated  on  charcoal,  sulphur 
fumes  are  given  off,  which  are  deposited  on  the  coal.  Dis- 
solves in  nitric  acid,  excepting  a  gray  residue. 

Dif.  Resembles  graphite,  but  differs  in  its  paler  color 
and  streak,  and  also  in  giving  fumes  of  sulphur  when  heated, 
as  well  as  by  its  solubility  hi  nitric  acid. 

Obs.  Occurs  in  granite,  gneiss,  mica  slate,  and  allied 
rocks  ;  also  in  granular  limestone.  It  is  found  at  Numedahl 
in  Sweden,  Arcndal  in  Norway,  in  Saxony,  Bohemia,  at 
Caldbeck  Fell  in  Cumberland,  and  in  the  Cornish  mines. 

In  the  United  States,  it  occurs  in  Maine  at  Blue  Hill 
Bay,  Camdage  farm,  Brunswick,  and  Bowdoinham  ;  in  New 
Hampshire  at  Westmoreland,  Landaff,  and  Franconia ;  in 
Massachusetts  at  Shutesbury  and  Brimfield  ;  in  Connecticut 
at  Haddam  and  Saybrook ;  in  New  York,  near  Warwick  ;  in 
New  Jersey,  near  the  Franklin  furnace. 

Molydic  ocher.  An  earthy  yellow  or  whitish  oxyd  of  molybdenum, 
(or  rather  molybdic  acid,)  occurring  only  as  an  incrustation.  Occurs 
at  Westmoreland,  N.  H. 

For  molybdate  of  lead,  see  page  268. 

18.    TUNGSTEN. 

Tungsten  is  found  in  combination  with  iron,  lead,  and  lime, 
constituting  wolfram,  (p.  225,)  tungstate  of  lead,  (p.  268,) 
and  tungstate  of  lime.  It  also  occurs  sparingly  in  some  ores 
of  columbium,  as  in  certain  varieties  of  the  minerals  pyro- 
chlore,  columbite,  and  yttro-columbite.  It  is  met  with  in 
very  small  quantities  as  an  ocher,  or  as  tungstic  acid,  form- 
ing a  yellow  powder  on  other  tungsten  ores. 

Lane's  mine,  Monroe,  Conn.,  the  adjoining  town  of  Hunt- 
ington,  and  Camdage  farm,  Blue  Hill  Bay,  Me.,  are  the  only 
American  localities  of  tungsten  ores  yet  discovered.  Lane's 
mine  affords  wolfram  and  the  calcareous  tungsten,  and  also 
the  tungstic  ocher.  These  ores  are  frequent  associates  of 
tin  ore. 

No  use  in  the  arts  has  been  made  of  this  metal  or  its  com- 

What  is  its  composition  ?  How  does  it  differ  from  graphite  ?  What 
are  the  principal  ores  of  tungsten  ]  Has  any  use  been  made  of  them  in 
the  arts  ? 


300  METALS. 

pounds.  Tungstic  acid  is  a  fine  yellow,  even  brighter  than 
chrome  yellow  ;  but  it  turns  green  on  exposure  to  the  sun's 
rays. 

The  metal  tungsten  was  so  called  from  the  Swedish  word 
tung,  meaning  heavy,  the  calcareous  tungsten  being  pecu- 
liarly heavy  for  an  earthy  looking  mineral.  It  has  also  been 
called  scheelium,  in  honor  of  the  chemist  Scheele. 

Tungstate  of  lime.  In  square  octahedrons  ;  A  :  A=100° 
8'  and  130J  20'.  Cleavage  octahedral,  perfect.  Color  yel- 
lowish-white, or  brownish.  Brittle.  H— 4 — 4-5.  Gr= 
6-075.  Composition,  tungstic  acid  7-8,  lime  19-06.  Infu- 
sible  alone,  or  only  on  the  thinnest  edges.  Found  with  wol- 
fram at  Lane's  mine,  Munroe,  Conn. 

19.    VANADIUM. 

Vanadium  is  a  rare  metal.  It  is  found  in  nature  as  vanadic 
acid  in  the  vanadate  of  lead  (p.  268),  and  vanadate  of  cop- 
per (p.  285),  and  also  combined  with  lime.  The  last  men- 
tioned has  a  brick-red  color,  a  foliated  structure,  and  a  bright 
shining  luster. 

20.     TELLURIUM. 

Tellurium  occurs  native,  and  also  in  combination  with 
gold,  silver,  lead,  and  bismuth. 

The  metal  is  distinguished  from  arsenic  and  selenium 
by  giving  no  odor  before  the  blowpipe  ;  from  antimony 
and  bismuth  by  affording  fumes  in  a  glass  tube  below 
the  temperature  of  fusing  the  glass ;  and  when  heated  on 
charcoal,  the  oxyd  covers  the  coal  with  a  brownish-yellow 
oxyd,  like  bismuth  ;  but  the  inner  flame  directed  on  this  oxyd 
is  tinged  bright  green,  while  bismuth  gives  no  color.  This 
last  test  distinguishes  also  the  ores  of  tellurium. 

Native  tellurium  occurs  in  six-sided  prisms,  of  a  tin-white  color,  and 
also  massive.  Brittle.  H  =  2 — 25.  Gr  =  57—6-1.  Composition, 
tellurium  92-5.  iron  7'2,  gold  03.  From  Transylvania. 

Herrerite  is  a  green  mineral  from  Mexico,  containing  carbonic  acid 
31-9,  tellurium  55'6,  pejoxyd  of  nickel  12'3.  It  is  supposed  to  be  a 
mechanical  mixture. 

In  what  minerals  is  vanadium  found  ?  How  does  tellurium  occur  in 
nature?  How  is  this  metal  distinguished  from  arsenic  and  selenium  ? 


OHES    OF    ANTIMONX  301 

21.     ANTIMONY. 

The  metal  antimony  is  occasionally  found  native.  It  is 
usually  combined  with  sulphur,  or  sulphur  and  lead.  It  is 
also  found  in  combination  with  arsenic,  oxygen,  and  lime  ; 
also  with  nickel,  silver,  and  copper. 

It  rises  easily  in  white  fumes  before  the  blowpipe  with- 
out odor,  and  in  one  or  both  of  these  particulars,  it  is  dis- 
tinguished from  other  vaporizable  metals.  The  ores  fuse 
very  easily,  and  all  evaporate,  some  giving  off  fumes  of  sul- 
phur. Specific  gravity  below  7. 

NATIVE    ANTIMONY. 

Rhombohedral.  .Usually  massive,  with  a  distinct  lamellar 
structure.  Color  and  streak  tin-white.  Brittle.  H  =  3— 
3-5.  Gr=6-6 — 6-75. 

Composition  :  pure  antimony,  often  with  a  little  silver  or 
iron.  Fuses  easily  and  passes  off  in  white  fumes. 

Obs.  Occurs  in  veins  of  silver  and  other  ores  in  Dau- 
phiny,  Bohemia,  Sweden,  the  Hartz,  and  Mexico. 

GRAY  ANTIMONY. — Sulphuret  of  Antimony. 

Trimetric.  In  right  rhombic  prisms,  with  striated  lateral 
faces.  M  :  M  =  90°  45'.  Cleavage  in  the  direction  of  the 
shorter  diagonal,  highly  perfect.  M  :  e  =  145°  29' 
e  :  e  =  109°  16'.  Commonly  divergent,  columnar  or 
fibrous.  Sometimes  massive  granular. 

Color  and  streak  lead-gray;  liable  to  tarnish. 
Luster  shining.  Brittle  ;  but  thin  laminae,  a  little 
flexible.  H=2.  Gr=4'5 — 4-62. 

Composition :  antimony  73,  sulphur   27.     Fuses 
readily  in  the  flame  of  a  candle.     On  charcoal  it  is  absorbed, 
giving  off  white  fumes  and  a  sulphur  odor. 

Dif.  Distinguished  by  its  extreme  fusibility  and  its  vapo- 
rizing before  the  blowpipe. 

Obs.  Gray  antimony  occurs  in  veins  with  ores  of  silver, 
lead,  zinc,  or  iron,  and  is  often  associated  with  heavy  spar 

How  does  antimony  occur  in  nature  ?     What  are  its  blowpipe  char- 
acters  ?     What  are  the  characters  of  native  antimony  ?     What  is  the 
crystallization  and  appearance  of  gray  antimony  ?     What  is  its  compo- 
sition ?     How  is  it  distinguished  ?     How  does  this  ore  occur  ? 
26 


302  METALS. 

or  quartz.  Its  most  celebrated  localities'  are  at  Schemnitz, 
Kremnitz,  and  Felsobanya,  in  Hungary.  It  also  occurs  in 
the  Hartz,  Auvergne,  Cornwall,  Spain. 

In  the  United  States,  it  has  been  found  sparingly  at  Car- 
mel,  Me.,  Lyme,  N.  H.,  and  at  "  Soldier's  Delight,"  Md. 

Uses.  This  ore  affords  nearly  all  the  antimony  of  com- 
merce. 

SULPHURETS  OF  ANTIMONY  AND  LEAD. 

There  are  several  sulphurets  of  antimony  and  lead,  all  of  which  fuae 
very  easily,  giving  off  white  fumes,  with  a  sulphur  odor,  and  covering 
the  charcoal  with  yellowish  oxyd  of  lead.  The  color  and  streak  are 
between  lead-gray  and  dark  steel-gray. 

Jamesonite.  Occurs  in  right  rhombic  crystals,  and  also  fibrous  or 
columnar.  M  :  M=101°  20'.  Streak  and  color  steel-gray.  H=2 — • 
2'5.  Gr=5  5 — 5-8.  Contains  antimony  35  per  cent.,  lead  41,  and 
sulphur  23.  From  Cornwall,  Siberia,  and  Hungary. 

Feather  ore.  In  fine  capillary  crystallizations,  like  a  cobweb,  or  plu- 
mose. Color  dark  lead-gray.  Contains  antimony  31,  lead  47,  sulphur 
20.  From  the  Eastern  Hartz. 

Boulangerite.  In  plumose  masses.  Color  bluish  lead-gray.  H= 
2'5.  Gr=5'97.  Contains  antimony  2544,  lead  55- 6,  sulphur  19.  From 
Molicres  in  France  ;  also  from  Lapland  and  Russia. 

Plagionite.  In  oblique  rhombic  crystals.  M  :  M=120°  49'.  Color 
blackish  lead-gray.  Brittle.  H=2  5.  Gr=5  4.  Contains  antimony 
38,  lead  41,  sulphur  21.  From  Wolfsberg  in  the  Hartz. 

Zinkenite.  In  hexagonal  prisms ;  also  fibrous  and  massive.  Color 
steel-gray.  H=3 — 35.  Gr=5'3.  Contains  antimony  45,  lead  32, 
sulphur  23.  From  Wolfsberg  in  the  Hartz. 

Geocronite,  Kilbrickenite.  Massive,  with  an  imperfect  cleavage,  and 
also  granular.  Color  light  gray.  H=2 — 2'5.  Gr=5'9 — 6'4.  Con- 
tains antimony  14'5,  (which  is  sometimes  partly  replaced  by  arsenic,) 
lead  69,  sulphur  16'5.  From  Gallicia,  Kilbricken  in  Ireland,  and  Sala 
in  Sweden. 

Kobellite.  Radiated  like  gray  antimony.  Gr=6'3.  Contains  33 
percent,  of  sulphuret  of  bismuth,  along  with  46  of  sulphuret  of  lead,  and 
13  of  sulphuret  of  antimony.  From  Hvena  in  Sweden. 

Steinmannite.  In  cubes  with  cubic  cleavage,  and  massive.  H=2'5. 
Gr=6'83.  Color  lead-gray.  Affords  before  the  blowpipe  fumes  of 
sulphur  and  antimony,  and  a  globule  of  lead  containing  silver. 

Besides  these,  there  are  also — 

Berthierite,  (called  also  haidingerite ,}  which  resembles  gray  antimony, 
but  contains  27  per  cent,  of  sulphuret  of  iron  with  sulphuret  of  antimony. 
Another  species  contains  15  per  cent,  of  sulphuret  of  iron.  From 
Chazelles  in  Auvergne. 

Arsenical  antimony.  Granular,  massive  ;  color  tin-white  or  reddish- 
gray.  H  =  2 — 4.  Gr=6'2.  Composition,  antimony  37'9,  arsenic 
62' 1.  From  Allemont  and  Bohemia. 

Are  there  other  ores  of  antimony  ]    What  is  their  general  constitution  I 


ORES    OF   ANTIMONY 


WHITE    ANTIMONY. 

In  white,  grayish,  or  reddish  rectangular  crystals,  with 
perfect  cleavage,  affording  a  rhombic  prism  of  136°  38 . 
Also  in  tabular  masses,  and  columnar  and  granular.  H  = 
2'5 — 3.  Gr=5'57.  Luster  adamantine  to  pearly.  From 
Bohemia,  Saxony,  Hungary,  Dauphiny.  It  is  an  oxyd  of 
antimony  containing  84*3  per  cent,  of  antimony. 

The  antimonic  and  antimonous  acids  have  been  observed  in  a 
white  pulverulent  form.  Stiblite  is  the  name  of  a  compound  of  oxyd 
of  antimony  and  an  antimony  acid,  (an  antimonate  of  antimony.) 

Red  antimony  is  a  compound  of  oxyd  and  sulphuret  of  antimony. 
Occurs  usually  in  tufts  of  capillary  crystals,  or  in  flakes.  Color  cherry- 
red  ;  streak  brownish-red.  Luster  adamantine.  H=l — 1-5.  Gr=4'4 

4'6.  From  Hungary,  Dauphiny,  Saxony,  and  the  Hartz. 

Romeine  is  an  antimonate  of  lime.  It  occurs  in  Piedmont  in  groups 
of  minute  square  octahedral  crystals,  of  a  hyacinth  or  honey-yellow 
color.  Scratches  glass. 

Antimojiate  of  lead.  A  rare  mineral  consisting  of  antimonic  acid 
31*7,  oxyd  of  lead  61'8,  water  6'5.  Amorphous,  compact.  Color  yel- 
low ;  also  grayish,  green,  or  black.  Luster  resinous.  Gr=4.6— 4*76. 
From  Nertschinsk,  Russia.  » 

Antimonophyllite  occurs  in  grayish-white,  thin,  six-sided  prisms. 
Contains  oxyd  of  antimony. 

GENERAL  REMARKS  ON  ANTIMONY  AND  ITS  ORES. 

The  antimony  of  commerce  is  obtained  from  the  sulphuret  of  anti- 
mony. This  ore  is  worked  at  Schemnitz  and  Kremnitz  in  Lower  Hun- 
gary, where  it  is  associated  with  ores  of  silver,  copper,  lead,  zinc,  and 
manganese,  and  some  gold.  This  region  affords  6000  qointals  of  an- 
timony annually.  It  has  also  been  brought  in  considerable  quantities 
from  Borneo  to  Boston  and  then  reduced.  Several  mines  have  been 
opened  and  abandoned  in  Auvergne  and  Dauphiny,  but  they  are  not  now 
worked.  There  are  also  mines  in  France  and  Great  Britain. 

To  obtain  the  crude  antimony  of  the  shops,  the  ore  is  placed  in 
crucibles  having  a  hole  at  bottom,  and  these  are  inserted  in  other  ves- 
sels :  heat  is  applied  above,  and  the  ore  melts  from  its  gangue  and  flows 
into  the  vessel  below,  where  it  becomes  solid.  It  is  not  altered  in  com- 
position. It  is  reduced  by  carefully  roasting  the  crude  antimony  in  a 
reverberatory  furnace,  and  thus  obtaining  a  gray  oxyd.  This  oxyd  is 
then  mixed  with  a  tenth  of  its  weight  of  crude  tartar,  placed  in  large 
melting  pots,  and  heated  in  a  wind  furnace.  The  metal  antimony 
(called  regains  of  antimony)  is  thus  obtained  pure,  excepting  generally 
some  little  iron.  By  melting  it  again  with  one-Fourth  its  weight  of  the 
oxyd  of  antimony,  the  impurities  separate  and  form  a  slag  above,  leav- 
ing the  metal  beneath.  It  is  a  silver- white,  brittle  metal,  coarsely  crys- 
talline in  texture.  It  fuses  at  about  800°  F. 

What  ore  affords  the  antimony  of  commerce  ?  Where  is  it  mostly 
obtained  ?  How  is  crude  antimony  obtained,  and  how  reduced  ? 


304 

The  sulphuret  may  be  reduced  also  by  heating  it  with  iron  filings  ; 
the  iron  takes  the  sulphur  and  liberates  the  antimony. 

Antimony  forms  an  important  part  of  type  metal.  The  proportions 
vary  in  different  establishments  ;  they  have  been  stated  at  1  of  antimony 
to  4  to  12  of  lead.  A  liltle  tin  is  sometimes  used,  and  also  bismuth  for 
the  best  type.  The  alloy  is  specially  fitted  for  this  purpose  because 
it  expands  a  little  on  cooling,  filling  well  the  mould  and  making  a 
sharp,  clear  letter.  The  Britannia  metal,  which  has  superseded  the 
use  of  pewter,  consists  of  100  parts  of  the  best  block  tin,  with  &  parts  of 
the  metal  antimony,  and  either  2-J^  parts  of  each  copper  and  brass,  or  2 
parts  of  copper  and  bismuth.  A  soft  solder  is  used  in  the  manufacture 
of  Britannia  ware,  consisting  of  fine  tin  alloyed  with  about  30  per  cent,  of 
lead.  Antimony  with  tin,  forms  the  metal  on  which  music  is  engraved. 

The  glass  of  antimony,  which  is  much  used  for  making  pharmaceu- 
tical preparations,  is  a  mixture  of  the  sulphuret  and  oxyd  of  antimony, 
usually  85  of  the  latter  to  15  of  the  former  ;  it  is  formed  by  partially  re- 
ducing the  sulphuret  to  an  oxyd  by  roasting,  and  then  raising  the  heat 
till  the  whole  melts. 

Antimony  in  the  condition  of  tartrate  of  antimony  and  potassa,  is  the 
tartar  emetic  of  the  apothecary. 

22.     ARSENIC. 

The  metal  arsenic  occurs  native,  and  united  with  oxygen 
or  sulphur.  It  also  occurs  in  combinations  with  various 
metals,  as  iron,  cobalt,  nickel,  silver,  copper,  manganese,  and 
antimony ;  also  as  an  acid  in  combination  with  the  oxyds  of 
iron,  cobalt,  nickel,  copper,  lead,  and  with  lime.  Its  ores  are 
distinguished  readily  by  giving  off  an  odor  like  garlic  when 
heated  on  charcoal  before  the  blowpipe.  Its  compounds  with 
the  metals  and  bases  have  already  been  described. 

NATIVE    ARSENIC. 

Rhombohedral.  R  :  R  =  114°  26'.  Cleavage  basal,  im- 
perfect. Also  massive,  columnar,  or  granular. 

Color  and  streak  tin-white,  but  usually  dark  grayish  from 
tarnish.  Brittle.  H  =  3'5.  Gr=5-65 — 5-95. 

Volatilizes  very  readily  before  fusing,  with  the  odor  of 
garlic  ;  also  burns  with  a  pale  bluish  flame  when  heated  just 
below  redness. 

Obs.  Occurs  with  silver  and  lead  ores.  It  is  found  in 
considerable  quantities  at  ihe  silver  mines  of  Freiberg  and 

How  is  crude  antimony  reduced  1  For  what  is  antimony  used  1 
What  is  Britannia  metal  ?  How  does  arsenic  occur  in  the  mineral 
kingdom  1  How  is  it  distinguished  ?  Describe  native  arsenic.  With 
what  is  it  found  ? 


ORES    OF    ABSENIC.  305 

Schneeberg ;  also  in  Bohemia,  the  Hartz,  at  Kapnik  in  Up- 
per Hungary,  in  Siberia  in  large  masses,  and  elsewhere. 

In  the  United  States,  it  has  been  observed  at  Haverhill, 
N.  H.,  in  juica  slate,  and  also  at  Jackson  in  the  same  state. 

The  name  arsenic  is  derived  from  the  Greek  arsenikon, 
or  arrenikon,  masculine,  a  term  applied  to  orpiment,  a  sul- 
phuret  of  arsenic,  on  account  of  its  potent  properties. 

WHITE  ARSENIC. — Arsenous  Acid. 

In  minute  capillary  crystals,  and  botryoidal  or  stalactitic. 
Color  white.  Soluble;  taste  astringent,  sweetish.  H  = 
1*5 — Gr==3'7.  Composition,  arsenic  75-8,  oxygen  24*2. 

This  is  the  same  compound  with  the  common  arsenic  of 
the  shops.  It  is  found  but  sparingly  native,  accompanying 
ores  of  silver,  lead  and  arsenic  in  the  Hartz,  Bohemia,  and 
elsewhere. 

Uses.     It  is  a  well  known  poison. 

Pharmacolite,  is  an  arsenate  of  lime,  occurring  in  white  or  grayish 
crystals.  H=2— 2  5  ;  Gr=2  6— 2'8. 

Haidingerite.     Haidingerite  is  another  arsenate  of  lime. 

SULPHURETS    OF    ARSENIC. 

There  are  two  sulphurets  of  arsenic. 

Orpiment  or  the  yellow  sulphuret  of  arsenic.  In  foliated 
masses,  and  sometimes  in  prismatic  crystals, 
with  a  perfect  diagonal  cleavage.  Color  and 
streak  fine  yellow.  Luster  brilliant  pearly, 
or  metallic  pearly  on  the  face  of  cleav- 
age. Subtransparent  to  translucent :  sectile. 
H=l-5— 2.  Gr=3-4— 3-5.  Composition, 
sulphur  39' 1,  arsenic  6O9.  Wholly  evapo- 
rates before  the  blowpipe  with  an  alliaceous 
odor,  and  on  charcoal  burns  with  a  blue 
flame.  From  Hungary,  Koordistan  in  Turkey  in  Asia, 
China,  and  South  America.  Occurs  at  Edenville,  N.  Y.,  as 
a  yellow  powder,  resulting  from  the  decomposition  of  arseni- 
cal iron. 

Realgar,  or  Red  sulphuret  of  arsenic.  In  oblique  prisms, 
and  also  massive  :  cleavage  much  less  perfect  than  in  orpi- 
ment.  Color  fine  clear  red,  aurora  red  to  orange.  Luster 
resinous.  Transparent  to  translucent.  H=1'5 — 2.  Gr  = 

What  is  white  arsenic  ?  What  are  the  characters  of  orpiment  1 
«vhat  of  realgar  ? 

26* 


306  METALS. 

3 -35 — 3*65.  Composition,  sulphur  30,  arsenic  70.  Like 
the  preceding  before  the  blowpipe.  From  Hungary,  Bohe- 
mia, Saxony,  the  Hartz,  Switzerland,  and  Koordistan  in 
Asiatic  Turkey.  It  has  been  observed  in  the  lavas  of 
Vesuvius. 

GENERAL  REMARKS  ON  ARSENIC  AND  ITS  ORES. 

Arsenic  is  most  used  in  the  state  of  arsenous  acid,  called  also  white 
arsenic.  This  substance  is  prepared  principally  at  Joachimstahl  in  Bo- 
hemia, and  in  Hungary,  and  is  obtained  from  arsenical  cobalt  and  iron. 
These  ores  are  roasted  in  reverberatory  .furnaces,  (the  cobalt  ores  for  the 
cobalt  they  contain,)  and  the  vapors  (which  are  white  arsenic)  are  con- 
densed in  a  long  horizontal  chimney ;  after  undergoing  a  second  subli- 
mation, usually  with  a  little  potash,  it  is  ready  for  commerce.  The 
manufacture  is  very  destructive  to  life,  and  those  engaged  in  it  seldom 
live  over  30  or  35  years. 

White  arsenic,  besides  its  use  as  a  poison,  is  employed  as  a  flux  for 
glass,  and  also  to  give  a  peculiar  milky  or  porcelain-like  hue  to  glass 
ware.  When  too  much  is  added,  the  glass  becomes  unsafe  for  domestic 
use. 

The  sulphurets  afford  valuable  pigments.  Orpiment  is  the  basis  of 
the  pigment  called  king's  yellow.  The  ammoniacal  solution  of  orpi- 
ment  is  recommended  tor  dyeing.  It  affords  a  yellow  which  is  perma- 
nent, but  is  injured  by  soap.  Realgar  is  used  in  the  preparation  of  the 
pyrotechnical  compound  called  white  Indian  fire,  which  consists  of  24 
parts  of  saltpeter,  7  of  sulphur,  and  2  of  realgar,  finely  powdered  and  well 
mixed.  It  burns  with  a  white  flame  and  great  brilliancy. 

The  sulphurets  are  obtained  for  commerce  by  distilling  arsenical 
pyrites  and  iron  pyrites,  (sulphuret  of  iron,)  or  from  white  arsenic  and 
rough  brimstone  ;  the  product  is  realgar  or  orpiment  according  to  the 
proportions  employed. 

A  combination  of  the  arsenous  acid  with  oxyd  of  copper,  obtained  by 
mixing  arsenite  of  potash  and  sulphate  of  copper,  produces  a  fine  green 
pigment  called  Scheele's  green. 

Arsenic  is  mixed  in  a  small  quantity  (less  than  1  per  cent.)  with  lead, 
in  the  manufacture  of  shot,  as  it  renders  the  metal  more  ready  to  break 
up  into  minute  drops  when  caused  to  fall  through  a  sieve  from  a  height, 
as  in  the  shot  tower,  and  the  grains  assume  a  more  spherical  form 
on  the  descent,  besides  being  less  malleable  than  if  of  pure  lead.  In 
shot  towers,  the  melted  lead  falls  usually  about  150  feet  into  a  vessel 
of  water  at  the  bottom  of  the  tower.  They  are  afterwards  sifted  in 
sieves  of  different  degrees  of  fineness,  from  No.  1,  the  finest,  to  No.  12, 
and  thus  the  several  sizes  of  shot  are  separated  and  assorted.  There 
are  still  some  imperfect  shot  among  them  ;  and  to  separate  them  the 
shot  are  made  by  a  shake  to  roll  from  trays  a  little  inclined  into  a  bin ; 
those  that  are  imperfect  roll  sluggishly  and  are  behind  in  the  movement, 
and  are  thus  separated  to  be  melted  over  again. 

How  do  orpiment  and  realgar  differ  in  composition  ?  From  what  ores 
is  arsenic  obtained  ?  How  is  white  arsenic  prepared  1  For  what  is 
arsenic  used  ]  How  are  shot  made  1 


PLATINUM.  307 

2.     NOBLE  METALS. 

1.    PLATINUM.— IRIDIUM.— PALLADIUM. 

NATIVE    PLATINUM. 

In  flattened  or  angular  grains  or  irregular  masses.  Crys- 
talline form  cubic,  and  also  rhombohedral,  the  metal  being 
dimorphous.  Cleavage  none. 

Color  and  streak  pale  or  dark  steel-gray.  Luster  metallic, 
shining.  Ductile  and  malleable.  H=4 — 4*5.  Gr  =  16 — 
19. 

Composition.  Platinum  is  usually  combined  with  more  or 
less  of  the  rare  metals  Iridium,  Rhodium,  Palladium,  and 
Osmium,  besides  copper  and  iron,  which  give  it  a  darker 
color  than  belongs  to  the  pure  metal,  and  increase  its  hard- 
ness. A  Russian  specimen  afforded,  platinum  78'9,  iridium 
5'0,  osmium  and  iridium  1-9,  rhodium  0'9,  palladium  0'3, 
copper  0*7,  iron  11'0  =  98'75. 

Platinum  is  soluble  in  heated  aqua  regia.  It  is  one  of 
the  most  infusible  substances  known,  being  wholly  unaltered 
before  the  blowpipe.  It  is  very  slightly  magnetic,  and  this 
quality  is  increased  by  the  iron  it  may  contain. 

Dif.  Platinum  is  at  once  distinguished  by  its  malleabil- 
ity and  extreme  infusibility. 

Obs.  Platinum  was  first  detected  in  grains  in  the  alluvial 
deposits  of  Choco  and  BarbaQoa  in  South  America,  where  it 
received  the  name  platina,  a  diminutive  of  the  word  plata, 
meaning  silver.  It  was  discovered  by  Ulloa,  a  Spanish 
traveler  in  America,  in  the  year  1735,  and  was  made  known 
in  Europe  in  1748.  It  has  since  been  found  in  the  Urals, 
on  Borneo,  in  the  sands  of  the  Rhine,  and  in  those  of  the  river 
Jocky,  St.  Domingo  ;  and  recently  traces  have  been  observed 
in  the  United  States,  in  North  Carolina. 

The  Ural  localities  of  Nischne  Tagilsk,  and  Goroblagodat, 
have  afforded  much  the  larger  part  of  the  platinum  of  com- 
merce. It  occurs,  as  elsewhere,  in  alluvial  beds  ;  but  the 
courses  of  platiniferous  alluvium  have  been  traced  to  a  great 
extent  up  Mount  La  Martiane,  which  consists  of  crystalline 

What  is  the  condition  and  appearance  of  native  platinum?  What 
is  said  of  its  crystallization  ?  What  is  its  specific  gravity  ?  With  what 
is  it  usually  combined  ?  Where  and  when  was  it  first  found  ?  Where 
else  does  it  occur  ? 


308  METALS. 

rocks,  and  is  the  origin  of  the  detritus.  One  to  three  pounds 
are  procured  from  3700  pounds  of  sand. 

Though  commonly  in  small  grains,  masses  of  considerable 
size  have  occasionally  been  found.  A  ma&s  weighing  1088 
grains  was  brought  by  Humboldt  from  South  America  and 
deposited  in  the  Berlin  Museum.  Its  specific  gravity  was 
18*94.  In  the  year  1822,  a  mass  from  Condoto  was  de- 
posited in  the  Madrid  museum,  measuring  2  inches  and  4 
lines  in  diameter,  and  weighing  11,641  grains.  A  more 
remarkable  specimen  was  found  in  the  year  1827  in  the 
Urals,  not  far  from  the  Demidoff  mines,  which  weighed  ll£ 
(more  accurately,  11*57)  pounds  troy;  and  similar  masses 
are  now  not  uncommon.  The  largest  yet  discovered  weighed 
21  pounds  troy;  it  is  in  the  Demidoff  cabinet. 

Russia  affords  annually  about  80  cwt.  of  platinum,  which 
is  nearly  ten  times  the  amount  from  Brazil,  Columbia,  St. 
Domingo,  and  Borneo.  Borneo  affords  six  or  eight  hundred 
pounds  per  year. 

The  North  Carolina  platinum  was  found  with  gold  in 
Rutherford  county.  It  was  a  single  reniform  granule,  weigh- 
ing 2*54  grains.  Other  instances  are  reported  from  the 
southern  gold  region. 

Uses.  The  infusibility  of  platinum  and  its  resistance  to 
the  action  of  the  air,  and  moisture  and  most  chemical  agents, 
renders  it  of  great  value  for  the  construction  of  chemical  and 
philosophical  apparatus.  The  large  vessels  employed  in  the 
concentration  of  sulphuric  acid  are  now  made  of  platinum,  as 
it  is  unaffected  by  this  corrosive  acid.  It  is  also  used  for 
crucibles  and  capsules  in  chemical  analysis ;  for  galvanic  bat- 
teries ;  as  foil  or  worked  into  cups  or  forceps  for  supporting 
objects  before  the  blowpipe.  It  alloys  readily  when  heated 
with  iron,  lead,  and  several  of  the  metals,  and  is  also  at- 
tacked by  caustic  potash,  and  phosphoric  acid,  in  contact  with 
carbon ;  and  consequently  there  should  be  caution  when  heat- 
ing it  not  to  expose  it  to  these  agents. 

It  is  employed  for  coating  copper  and  brass ;  also  for 
painting  porcelain  and  giving  it  a  steel  luster,  formerly  highly 
prized.  It  admits  of  being  drawn  into  wire  of  extreme  ten- 
uity: Dr.  Wollaston  obtained  a  wire  not  exceeding  a  two- 
thousandth  of  an  inch  in  diameter. 

Platinum  is  coined  in  Russia,  but  is  not  a  legal  tender. 

What  are  the  uses  of  platinum  1 


PLATINUM.  309 

The  coins  have  the  value  of  11  and  22  rabies  each.  The 
amount  coined  from  1826  to  1844  equals  2£  millions  of 
dollars. 

For  many  years  after  its  discovery,  platinum  was  almost  a 
useless  metal  on  account  of  the  difficulty  of  obtaining  it  in 
masses.  The  grains  weld  when  heated,  but  because  of  their 
small  size,  this  was  interminable  labor,  and  moreover  the 
metal  wa^  not  pure.  Dr.  Wollaston  introduced  the  process 
now  in  use,  which  consists  in  dissolving  the  metal  in  nitro- 
muriatic  acid,  and  throwing  down  from  the  solution  an  orange 
precipitate  by  means  of  muriate  of  ammonia.  This  precipi- 
tate (a  double  chlorid  of  platinum  and  ammonium)  is  then 
heated  and  thus  reduced  to  the  metallic  state  ;  the  platinum  is 
now  in  an  extremely  minute  state  of  division.  This  black 
powder  ("  spongy  platinum")  is  next  compressed  in  steel 
moulds  by  the  aid  of  heat  and  strong  pressure  ;  and  when 
sufficiently  compact,  is  forged  under  the  hammer  and  then  re- 
duced at  last  to  solid  masses. 

This  metal  fuses  readily  before  the  "  compound  blowpipe ;" 
and  Dr.  Hare  succeeded  in  1837  in  melting  twenty-eight 
ounces  into  one  mass.*  The  metal  was  almost  as  malle- 
able and  as  good  for  working  as  that  obtained  by  the  other 
process  ;  it  had  a  specific  gravity  of  19*8.  He  afterwards 
succeeded  in  obtaining  from  the  ore  masses  which  were  90 
per  cent,  platinum,  and  as  malleable  as  the  metal  in  ordinary 
use,  though  somewhat  more  liable  to  tarnish,  owing  to  some 
of  its  impurities. 

Platin-iridium.  Grains  of  indium  have  been  obtained  at  Nischne 
Tagilsk,  consisting  of  76'8  indium,  and  19'64  platinum,  with  some 
palladium  and  copper.  A  similar  platin-iridium  has  been  obtained  at 
Ava  in  the  East  Indies.  Another  from  Brazil  contained  27'8  iridium, 
55'5  platinum,  and  6'9  of  rhodium. 

Iridosmine.  A  compound  of  iridium  and  osmium  from  the  platinum 
mines  of  Russia,  South  America  and  the  East  Indies.  The  crystals 
are  pale  steel-gray  hexagonal  prisms :  occurs  usually  in  flat  grains. 
H=6-7.  Gr=195— 2M.  Malleable  with  difficulty. 

The  composition  varies.  One  variety  contains  iridium  46'8,  osmium 
49  3,  rhodium  3'2,  iron  0'7.  Another,  iridium  25' 1,  osmium  74'9  ; 
another,  iridium  20,  osmium  80.  They  are  distinguished  by  their  su- 
perior hardness  from  the  grains  of  platinum,  and  also  by  the  peculiar 
odor  of  osmium  when  heated  with  niter. 

What  is  the  value  of  Russian  platinum  coins  1  How  is  platinum 
worked  into  masses? 

*  Amer.  Jour.  Sci.,  xxxiii,  195 ;  xxxvlii,  155, 163,  and  ii  ser.  iv,  39. 


310  METALS. 

The  metal  iridium  is  extremely  hard,  and  is  used  as  well  as  rhodium 
for  nibs  to  gold  pens.  Its  specific  gravity  is  2T8.  Rhodium  (1  to  2  per 
cent.)  gives  great  hardness  to  steel,  and  would  be  a  useful  metal  were 
it  more  abundant. 

NATIVE    PALLADIUM. 

Form  supposed  to  be  the  regular  octahedron.  Occurs 
mostly  in  grains,  apparently  composed  of  divergent  fibers. 
Color  steel-gray,  inclining  to  silver-white.  Ductile  and 
malleable.  H.  above  4*5.  Gr=ll'8— 12-2. 

Consists  of  palladium,  with  some  platinum  and  iridium. 
Fuses  with  sulphur,  but  not  alone. 

Obs.  Occurs  in  Brazil  with  gold,  and  is  distinguished 
from  platinum  with  which  it  is  associated  by  the  divergent 
structure  of  its  grains.  Selenpalladite  is  nothing  but  the 
native  palladium  ;  and  eugenesite  is  a  similar  compound. 

Uses.  This  metal  is  malleable,  and  when  polished  has  a 
splendid  steel-like  luster  which  does  not  tarnish.  A  cup 
weighing  3£  pounds  was  made  by  M.  Breant  in  the  mint  at 
Paris,  and  is  now  in  the  garde-mcuble  of  the  French  crown. 
In  hardness  it  is  equal  to  fine  steel.  1  part  fused  with  6  of 
gold  forms  a  white  alloy  ;  and  this  compound  was  employed, 
at  the  suggestion  of  Dr.  Wollaston,  for  the  graduated  part  of 
the  mural  circle,  constructed  by  Troughton  for  the  Royal 
Observatory  at  Greenwich.  Palladium  has  been  employed 
also  for  certain  surgical  intruments. 

Quite  large  masses  of  the  metal  palladium  are  brought 
from  Brazil.  Ijt  is  extracted  from  the  auriferous  sands  by 
first  fusing  it  with  silver,  and  consequently  forming  a  quater- 
nary alloy  of  gold,  palladium,  silver  and  copper,  which  is 
granulated  by  projecting  it  into  water.  By  means  of  nitric 
acid  all  but  the  gold  is  dissolved  ;  and  from  the  solution,  the 
silver  is  first  precipitated  by  common  salt  as  an  insoluble 
chlorid,  and  then,  after  separating  the  chloric!,  the  palladium 
and  copper  are  precipitated  by  plates  of  zinc.  This  pre- 
cipitate is  rcdissolved  in  nitric  acid,  an  excess  of  ammonia 
added,  and  then  hydrochloric  acid  sufficient  to  saturate  ;  a 
double  chlorid  of  palladium  and  ammonia  is  deposited  as 
a  crystalline  yellow  powder,  which  on  calcination  produces 
spongy  palladium. 


Describe  native  palladium  1     Where  and  how  does  it  occur  ?     How  is 
it  t'sed  1 


METALS.  311 


2.     GOLD. 

Gold  occurs  mostly  native,  being  either  pure  or  alloyed 
With  silver  and  other  metals.  It  is  occasially  found  miner- 
alized by  tellurium. 

NATIVE    GOLD. 

Monometric.  In  cubes,  without  cleavage.  Also  in  grains, 
thin  laminse  and  masses  ;  sometimes  filiform  or  reticulated. 

Color  various  shades  of  gold-yellow ;  occasionally  nearly 
silver- white,  from  the  silver  present.  Very  ductile  and  mal- 
leable. H  =  2-5 — 3.  Gr=12 — 20,  varying  according  to 
the  metals  alloyed  with  the  gold. 

Composition.  Native  gold  usually  contains  silver,  and  in 
very  various  proportions.  The  finest  native  gold  from  Rus- 
sia yielded  gold  98-96,  silver  0'16,  copper  0'35,  iron  0'05  ; 
Gr=  19-099.  A  gold  from  Marmato  afforded  only  73-45 
per  cent,  of  gold,  with  26*48  percent,  of  silver  ;  Gr=12-666. 
This  last  is  in  the  proportion  of  3  of  gold  to  1  of  silver.  The 
following  proportions  also  have  been  observed  :  3£  to  1  ;  5 
to  1  ;  6  to  1  ;  8  to  1,  and  this  is  the  most  common  ;  12  to  1, 
also  of  frequent  occurrence. 

Copper  is  often  found  in  alloy  with  gold,  and  also  palla- 
dium and  rhodium.  A  rhodium-gold  from  Mexico  gave  the 
specific  gravity  15*5 — 16'8,  and  contained  34  to  43  per  cent, 
of  rhodium. 

Dif.  Iron  and  copper  pyrites  are  often  mistaken  for  gold 
by  those  inexperienced  in  ores.  Gold  is  at  once  distinguished 
by  being  easily  cut  in  slices  and  flattening  under  a  hammer. 
The  pyrites  when  pounded  are  reduced  to  powder ;  iron 
pyrites  is  too  hard  to  yield  at  all  to  a  knife,  and  copper  pyr- 
,ites  affords  a  dull  greenish  powder.  Moreover,  the  pyrites 
give  off  sulphur  when  strongly  heated,  while  gold  melts  with- 
out any  such  odor. 

Obs.  Native  gold  is  to  a  large  extent  obtained  from  allu- 
vial washings.  It  is  also  found  disseminated  through  certain 
rocks,  especially  quartz  and  talcose  rocks,  and  it  is  often 

In  what  condition  does  gold  occur  in  nature  ?  What  is  the  crystal- 
lization of  native  gold?  What  are  its  common  forms  in  the  rocks? 
Mention  its  characters.  With  what  is  it  alloyed  ?  How  is  gold  dis- 
tinguished from  iron  and  copper  pyrites?  How  is  gold  obtained,  and 
from  what  rocks  ? 


312  METALS. 

contained  in  pyrites,  constituting  the  auriferous  pyrites  ;  the 
detritus  affording  gold  dust  has  proceeded  from  some  gold- 
bearing  rocks. 

Gold  is  widely  distributed  over  the  globe.  It  occurs  in 
Brazil  (where  formerly  a  greater  part  of  that  used  was  ob- 
tained)  along  the  chain  of  mountains  which  runs  nearly  par- 
allel with  the  coast,  especially  near  Villa  Rica,  and  in  the 
province  of  Minas  Geraes  ;  in  New  Grenada  at  Antioquia, 
Choco,  and  Giron ;  in  Chili ;  sparingly  in  Peru  and  Mexico ; 
in  the  southern  of  the  United  States.  In  Europe,  it  is  most 
abundant  in  Hungary  at  Konigsberg,  Schemnitz  and  Felso- 
banya,  and  in  Transylvania  at  Kapnik,  Vorospatak,  and  Of- 
fenbanya ;  it  occurs  also  in  the  sands  of  the  Rhine,  the 
Reuss  and  the  Aar ;  on  the  southern  slope  of  the  Pennine 
Alps  from  the  Simplon  and  Monte  Rosa  to  the  valley  of 
Aosta  ;  in  Piedmont ;  in  Spain,  formerly  worked  in  Asturias ; 
in  the  county  of  Wicklow,  Ireland  ;  in  Sweden  at  Edelfors. 

In  the  Urals  are  valuable  mines  at  Berezof,  and  other 
places  on  the  eastern  or  Asiatic  flank  of  this  range,  and  the 
comparatively  level  portions  of  Siberia  ;  also  in  the  Altai 
mountains.  Also  in  the  Cailas  mountains  in  Little  Thibet. 

There  are  mines  in  Africa  at  Kordofan,  between  Darfour 
and  Abyssinia ;  also  south  of  Sahara  in  the  western  part  of 
Africa,  from  the  Senegal  to  Cape  Palmas  ;  also  along  the 
coast  opposite  Madagascar,  between  the  22  and  35  degrees 
south  latitude,  supposed  to  have  been  the  Ophir  of  the  time 
of  Solomon.  Other  regions  are  China,  Japan,  Formosa, 
Ceylon,  Java,  Sumatra,  western  coast  of  Borneo,  and  the 
Philippines. 

Nearly  all  the  gold  of  commerce  comes  from  Asiatic  Rus- 
sia, Brazil,  Bohemia  and  Transylvania,  Africa,  the  East 
India  Islands,  and  the  United  States  :  the  whole  amount  an- 
nually obtained  has  been  estimated  at  36  tons. 

The  Russian  mines  are  at  present  the  most  productive  in 
the  world.  They  are  principally  alluvial  washings,  and  these 
washings  seldom  yield  more  than  65  grains  of  gold  for  4000 
pounds  of  soil;  never  more  than  120  grains.  The  alluvium 
is  generally  most  productive  where  the  loose  material  is  most 
ferruginous.  The  mines  of  Ekaterinburg  are  in  the  parent 
rock — a  quartz  constituting  veins  in  a  half  decomposed 

What  is  said  of  the  distribution  of  gold  over  the  globe  ?  What  coun- 
tries afford  the  greatest  part  of  the  gold  of  commerce  ?  What  country 
yields  the  most  gold  at  the  present  time? 


GOLD.  313 

granite  called  "  beresite,"  which  is  connected  with  talcoso 
and  chloride  schists.  The  shafts  are  sunk  vertically  in  the 
beresite,  seldom  below  25  feet,  and  from  them  lateral  gal- 
lories  are  run  to  the  veins.  These  mines  afforded  between 
the  years  1725  and  1841,  679  poods  of  gold,  or  about  30,000 
pounds  troy.  The  whole  of  the  Russian  mines  yielded  in 
1842,  970  poods  of  golds,  or  42,000  pounds  troy,  half  of 
which  was  from  Siberia,  east  of  the  Urals.  In  1843,  the  yield 
was  nearly  60,000  pounds  troy,  or  about  $13,000,000;  in 
1845,  it  amounted  to  813,250,000;  and  in  1846,  to  1722-746 
poods,  equal  to  75,353  troy  pounds,  and  $16,500,000.* 

At  the  Transylvania  mines  of  Vorospatak,  the  gold  is  ob- 
tained by  mining,  and  these  mines  have  been  worked  since 
the  time  of  the  Romans. 

The  annual  yield  of  Europe,  exclusive  of  Russia,  is  not 
above  $1,000,000.  Austria  afforded  in  1844,  6785  marks. 
The  sands  of  the  Rhone,  Rhine,  and  Danube  contain  gold  in 
small  q'lantites.  The  Rhine  has  beerr  most  productive  be- 
tween  Bale  and  Manheim  ;  but  at  present  only  $9000  are 
extracted  annually.  The  sands  of  the  richest  quality  con- 
tain only  about  56  parts  of  gold  in  a  hundred  millions  ;  sands 
containing  less  than  half  this  proportion  are  worked.  The 
whole  amount  of  gold  in  the  auriferous  sand  of  the  Rhine 
is  estimated  at  $30,000,000,  but  it  is  mostly  covered  by  soil 
under  cultivation. 

Africa  yields  annually  at  least  4500  pounds  troy,  ($850,000,) 
and  Southern  Africa  1250  pounds,  ($235,000.) 

The  mines  of  South  America  and  Mexico  were  estimated 
by  Humboldt  to  yield  annually  about  $11,500,000  ;  but  the 
amount  has  much  diminished.  Brazil  of  late  has  furnished 
about  17,500  pounds  troy.  It  is  estimated  that  between 
1790  and  1830,  Mexico  produced  $31,250,000  in  gold,  Chili 
$13,450,000,  and  Buenos  Ayres  $19,500,000,  making  an 
average  annual  yield  of  $16,050,000. 

The  mines  of  the  United  States  have  produced  of  late  about 
a  million  of  dollars  a  year.  They  are  mostly  confined  to  the 

What  amount  was  furnished  by  Russia  in  1846  ?  What  is  the  an- 
nual yield  of  the  mines  of  the  United  States  I 

*  The  value  of  gold,  silver,  and  platinum  coined  in  Russia  from  1644 
to  1844,  at  present  rates,  equals  545..360,317  silver  rubles,  or  409,020,000 
|-    dollars ;  in   addition   to  which,  during  the  same  period,  the   value  of 
37,500,000  dollars  in  copper  was  coined. 


314  METALS. 

states  of  Virginia,  North  and  South  Carolina,  and  Georgia, 
or  along  a  line  from  the  Rappahannock  to  the  Coosa  in 
Alabama.  But  the  region  may  be  said  to  extend  north  to 
Canada  ;  for  gold  has  been  found  at  Canaan,  N.  H.,  DecU 
ham,  Mass.,  Albion,  Maine,  and  on  the  Chaudiere  river  in 
Canada. 

In  Virginia,  the  principal  deposits  are  in  Spotsylvania 
county,  on  the  Rappahannock,  at  the  United  States  mines  and 
at  other  places  to  the  southwest ;  in  Stafford  county,  at  the 
Rappahannock  gold  mines,  ten  miles  from  Falmouth  ;  in  Cul- 
pepper  county,  at  the  Culpepper  mines,  on  Rapidan  river  ;  in 
Orange  county,  at  the  Orange  grove  gold  mine,  and  at  the 
Greenwood  gold  mines  ;  in  Goochland  county,  at  Moss  and 
Busby's  mines  ;  in  Louisa  county,  at  Walton's  gold  mine  ; 
in  Buckingham  county,  at  Eldridge's  mine.  In  North  Car- 
olina, the  gold  region  is  mostly  confined  to  the  three  ranges 
of  counties  between  Frederick  and  Charlotte,  which  are  sit- 
uated  about  in  a  line  running  NE.  and  sw.,  parallel  nearly 
with  the  coast.  The  mines  at  Mecklenburg  are  principally 
vein  deposits  ;  those  of  Burke,  Lincoln,  and  Rutherford,  are 
mostly  in  alluvial  soil.  The  Davidson  county  silver  mine 
had  afforded  $7000  gold  in  1844.  In  Georgia,  the  Shelton 
gold  mines  in  Habersham  county  have  long  been  famous  ; 
and  many  other  places  have  been  opened  in  Rabun  and 
Hall  counties,  and  the  Cherokee  country.  In  South  Caro- 
lina, the  principal  gold  regions  are  the  Fairforest  in  Union 
district,  and  the  Lynch's  creek  and  Catawba  regions,  chiefly 
in  Lancaster  and  Chesterfield  districts ;  also  in  Pickens 
county,  adjoining  Georgia.  There  is  gold  also  in  eastern 
Tennessee. 

Viewing  the  gold  region  of  the  United  States  as  a  whole, 
it  is  perceived  that  it  ranges  along  the  Appalachians,  par- 
ticularly the  eastern  slope,  from  Maine  to  Alabama,  having 
nearly  a  northeast  and  southwest  course. 

The  table  here  given,  from  the  records  of  the  United 
States  mint  at  Philadelphia,  shows  the  amount  of  gold  af- 
forded by  the  gold  mines  of  the  country  since  1824.*  For 
an  account  of  the  California  mines,  see  Appendix,  p.  430. 

*  This  table  was  kindly  furnished  the  author  by  R.  M.  Patterson, 
Esq.,  Director  of  the  U.  S.  Mint  at  Philadelphia. 


• 


1 1 1 1 1 1 1 1 1 1 1 1 1  ig|3§S 

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II 


1 1 1 1 1 1  ii  i  ii  i 1 1 1 ' 1 1 


§O~  OOO        OO"*"?» 
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I      I     I     I 


316  IffETALS, 

The  gold  rock  of  the  United  States  is  to  a  great  extent  a 
micaceous  or  taicosc  schist,  with  veins  or  beds  of  quartz. 
The  gold  is  mostly  confined  to  these  veins,  though  also  found 
to  some  extent  in  the  rock  either  side.  The  schist  is  often 
half  decomposed  or  rusted.  The  quartz  is  usually  more  or 
less  cellular,  or  wanting  in  perfect  compactness,  and  some- 
times tabular ;  yet  it  is  at  times  quite  solid.  Iron  pyrites  is 
frequently  present,  and  by  decomposition  it  stains  the  rock 
with  iron  rusL  Other  minerals  often  associated  with  the 
gold,  are  copper  pyrites,  blende,  galena,  anglesite,  sulphur, 
(in  minute  yellow  crystals,  proceeding  from  the  decomposi- 
tion of  pyrites.)  Heavy  spar  is  sometimes  a  large  consti- 
tuent of  the  vein,  and  fluor  spar  is  now  and  then  present. 
The  peculiar  appearance  of  the  quartz,  somewhat  cellular, 
more  or  less  rusted,  and  its  position  in  veins  though  an  im- 
perfect shale,  and  generally  not  firmly  attached  to  the  en- 
closing walls,  affords  the  best  indication  of  the  presence  of 
gold,  though  the  absence  of  all  these  conditions  is  not  evi- 
dence that  no  gold  is  to  be  found.  The  grains  of  gold  may 
sometimes  be  seen  iu  the  cavities  of  the  quartz,  or  it  sparkles 
on  a  surface  of  fracture.  But  very  commonly  a  mass  of 
quartz  that  shows  nothing  to  the  eye,  yields  gold  on  trial. 

Masses  of  gold  of  considerable  size  have  been  found  in 
North  Carolina.  The  largest  was  discovered  in  Cabarras 
county  ;  it  weighed  twenty-eight  pounds  avoirdupois,  ("  steel- 
yard weight,"  equals  37  Ibs.  troy,)  and  was  8  or  9  inches  long 
by  4  or  5  broad,  and  about  an  iiich  thick.  In  Paraguay,  pieces 
from  1  to  50  pounds  weight  were  taken  from  a  mass  of  rock 
which  fell  from  one  of  the  highest  mountains.  Several 
specimens  weighing  16  pounds  have  been  found  in  the  Ural, 
and  one  of  27  pounds  :  and  in  the  valley  of  Taschku-Tar- 
ganka,  in  1842,  a  mass  was  detached  weighing  very  nearly 
100  pounds  troy.  This  mass  is  now  in  the  musuem  of  the 
Institute  of  Mining  Engineers  at  St.  Petersburgh. 

An  examination  of  a  gold  roclc  for  gold  is  an  extremely 
simple  process.  The  rock  is  first  pounded  upjfine  and  sifted  ; 
a  certain  quantity  of  the  sand  thus  obtained  is  washed  in  a 
shallow  iron  pan,  and  as  the  gold  sinks,  the  material  above  is 
allowed  to  pass  off  into  some  receptacle.  The  largest 
part  of  the  gold  is  thus  left  in  the  angle  of  the  pan  ;  by  a  re- 
petition of  the  process  a  further  portion  is  obtained ;  and  when 

What  is  said  of  the  gold  rock  of  the  United  States  ? 


GOLD.  317 

the  bulk  of  sand  is  thus  reduced  to  a  manageable  quantity, 
the  gold  is  amalgamated  with  clean  mercury  ;  the  amalgam 
is  next  strained  to  separate  any  excess  of  mercury,  and  final- 
ly is  heated  and  the  mercury  expelled,  leaving  the  gold.  In 
this  way  by  successive  trials  with  the  rock,  the  proportion 
of  gold  is  quite  accurately  ascertained.  It  is  the  same  pro- 
cess used  with  the  larger  washings,  though  on  a  small  scale. 
Mercury  unites  readily  with  gold,  and  thus  separates  it  from 
any  associated  rock  or  sand  ;  and  it  is  employed  in  all  exten- 
sive gold  minings,  though  much  gold  may  be  cften  obtained 
by  simple  washing  without  amalgamation. 

The  operation  of  hand  washing  is  called  in  Virginia  pan- 
ning. With  a  small  iron  pan,  they  wash  the  earth  in  a  tub  or 
in  some  brook,  and  thus  extract  much  gold  from  the  gravel  or 
soil,  which  is  said  to  pan  well  or  pan  poorly  according  to  the 
result.  Masses  of  quartz,  with  no  external  indications  of 
gold,  examined  in  the  above  way  at  a  Virginia  mine,  afford- 
ed an  average  of  more  than  eight  dollars  to  the  bushel  of 
gold  rock. 

When  gold  is  alloyed  with  copper  or  silver,  the  mode  of 
assay  for  separating  the  copper  depends  on  the  process  of 
cupellation ;  and  that  for  separating  the  silver,  on  the 
power  of  nitric  acid  to  dissolve  silver  without  acting  on  the 
gold. 

The  process  of  cupellation  consists  in  heating  the  assay 
in  a  small  cup  (called  a  cupel,)  made  of  bone  ashes,  (or  in 
a  cavity  containing  bone  ashes,)  while  tJie  atmosphere  has 
free  access.  The  heated  metal  is  oxydated  by  the  air  pass- 
ing over  it,  and  the  oxyd  formed  sinks  into  the  porous  cup, 
1  leaving  the  precious  metal 

behind.     The  shape  of  the 

cupel  is  shown  in  fig.  1.    In 

order  to  fuse  the  alloy  and  3;j3 

still   have   the    atmosphere  \ i 

circulating  over  it,  the  cupel  is  placed  in  a  small  oven-shaped 

vessel,  called  a  muffle  (fig.  2  :)  it  is  of  infusible  stone  ware, 

and  has  a  number  of  oblong  holes,  through  which  to  admit 

,  the  flame  from  the   fire,  and  give  exit  to  the  atmosphere 

i  which  passes  into  it.     The  muffle  is  inserted  in  a  hole  fitting 

it  in  the  side  of  a  vertical  furnace,  with  the  open  mouth  out- 


How  is  a  rock  examined  for  gold  ?     What  are  the  processes  for  sepa- 
rating gold  from  silver  or  copper  ?     Describe  the  process  of  cupeliation. 
27* 


318  METALS. 


ward  and  even  nearly  with  the  exterior  surface  of  the  fur. 
nace.  The  fire  is  made  within  the  furnace,  below,  around, 
and  above  ;  and  after  heating  up,  the  cupel  is  put  in  the  muffle 
with  the  assay  in  its  shallow  cup-shaped  cavity.  It  thus  has 
the  heat  of  the  furnace  to  fuse  the  assay,  and  the  air  at  the 
same  time  is  drawn  in  over  it  through  the  large  opening  of 
the  muffle.  The  oxygen  of  the  atmosphere  unites  with  the 
lead  of  the  assay,  and  produces  an  oxyd,  which  oxyd  sinks 
into  the  cupel,  leaving  the  silver  or  gold  behind.  The  com- 
pletion of  the  process  is  at  once  known  by  the  change  of  the. 
assay  suddenly  to  a  bright  shining  globule* 

In  the  cupellation  of  gold  containing  copper,  lead  is  melted 
with  the  assay.  The  lead  on  being  fused  in  a  draft  of  air  oxy- 
dizes,  and  also  promotes  the  oxydation  of  the  copper,  and 
both  oxyds  disappear  in  the  pores  of  the  cupel  leaving  the 
gold  behind,  and  the  silver  alloyed  with  it.  In  this  process 
the  gold  is  melted  with  three  times  its  weight  of  silver,  (a 
quartation  as  it  is  termed,  the  gold  being  one  part  out  of  four 
of  the  alloy,)  in  order  by  its  diffusion  to  effect  a  more  com- 
plete removal  of  the  silver  as  well  as  the  contained  copper. 
The  cupel  is  placed  in  the  heated  furnace,  and  the  gold,  sil- 
ver, and  lead,  on  the  cupel ;  the  heat  is  continued  until  the 
surface  of  the  metal  is  quiet  and  bright,  when  the  cupella- 
tion is  finished  ;  the  metal  then  is  slowly  cooled  and  re- 
moved. The  button  obtained,  after  annealing  it  by  bringing 
it  to  a  red  heat,  is  rolled  out  into  a  thin  plate  and  boiled  in 
strong  nitric  acid.  This  process  is  repeated  two  or  three 
times  with  a  change  of  the  acid  each  time,  and  the  silver  is 
thus  finally  removed.  At  the  United  States  mint,  half  a 
gramme  of  the  gold  is  submitted  to  assay.  The  assay-gold 
and  quartation. silver  are  wrapped  in  a  sheet  of  lead  weigh- 
ing about  ten  times  as  much  as  the  gold  under  assay.  After 
cupellation,  the  plate  of  gold  and  silver,  loosely  rolled  into  a 
ooil,  is  boiled  for  20  minutes  in  4£  oz.  of  nitric  acid,  of  20  to 
22 ~'  Beaume  ;  the  acid  is  then  poured  off  and  another  por- 
tion of  stronger  acid  is  added,  about  half  the  former  quantity, 
and  boiled  10  minutes  ;  then  the  same  again.  The  gold 
thus  purified  is  washed  and  exposed  to  a  red  heat,  for  the 
purpose  of  drying  and  annealing  it,  and  then  weighed. 

Uses.  The  uses  of  gold  are  well  known  ;  and  also  that 
it  owes  a  great  part  of  its  value  to  its  extreme  malleability, 
and  the  fact  of  its  not  tarnishing  on  exposure.  Although  a 
costly  metal,  it  is  one  of  the  cheapest  means  of  ornament, 


SILVER    ORES,  31i 

<on  aecxmat  of  the  thinness  of  the  leaves  into  which  it 
is  beaten.  A  grain,  of  the  metal  may  be  made  to  cover 
56 1  square  inches  of  surface,  and  tlie  thinnest  leaf  is  but 
1 -280,000th  of  an  inch  thick. 

Perfectly  pure  gold  is  denominated  gold  of  24  carats^  or 
Jine  gold.  If  it  contains  22  parts  of  pure  gold  to  2  of  silver, 
or  to  1  of  copper  and  1  of  silver,  it  is  said  to  be  22  carats  fine  ; 
so  also  for  20  carats  fine,  it  contains  20  parts  of  pure  gold. 
The  carat  is  c&vided  into  1,  £,  T'F,  ^  parts,  for  a  more  min- 
ute specification  of  the  quality  of  gold. 

The  standard  gold  of  the  United  States  consists  of  900 
pails  of  gold  to  100  of  an  alloy  of  copper  and  silver.  Th« 
eagle  (10  dollars)  contains  232  grains  of  fine  gold. 

Avrotcllnrite,  and  Graphic  T-ellariitm,  are  two  species  containing 
gold  combined  with  Tellurium. 

3.    SILVER. 

Silver  occurs  native  and  alloyed ;  also  mineralized  with 
sulphur,  selenium,  arsenic,  chlorine,  bromine,  or  iodine,  and 
|    in  combination  with  different  acids. 

The  ores  of  silver  fuse  easily  and  decompose  before  the 
blowpipe,  affording  a  globule  of  silver  either  alone  or  with 
soda ;  the  globule  is  known  to  be  silver  by  its  flattening 
out  readily  under  a  hammer,  and  also  by  its  sectility.  The 
species  vary  in  specific  gravity  from  5*5  to  10'5. 

NATIVE    SILVER, 

Monometric.  In  octahedrons.  No  cleavage  apparent 
Occurs  often  in  filiform  and  arborescent  shapes,  the  threads 
having  a  crystalline  character  ;  also  in  laminae. 

Color  and  streak  silver- white  and  shining.  Sectile.  Mal- 
leable. H=2-5— 3.  Gr=10-3— 10-5. 

Composition  :  native  silver  is  usually  an  alloy  of  silver  and 
copper,  the  latter  ingredient  often  amounting  to  10  per  cent. 
It  is  also  alloyed  with  gold,  as  mentioned  under  that  metal. 
A  bismuth  silver  from  Copiapo,  S.  A.,  contained  16  per  cent, 
of  bismuth. 

What  surface  may  a  grain  of  gold  be  made  to  cover  ?  How  much 
pure  gold  is  there  in  the  American  eagle  ?  What  is  the  use  of  the 
term  carat  1  What  is  the  condition  of  silver  in  nature  ?  Describe  na- 
tive silver. 


320  METALS, 

Before  the  blowpipe  it  fuses  easily  and  affords  a  globule 
which  becomes  angular  on  cooling.  Dissolves  in  nitric  acid, 
from  which  it  is  precipitated  by  putting  in  a  clean  piece  of 
copper. 

Dif.  Distinguished  by  being  malleable  ;  from  bismuth 
and  other  white  native  metals  by  affording  no  fumes  before 
the  blowpipe  ;  by  affording  a  solution  with  muriatic  acid, 
which  becomes  black  on  exposure. 

Obs.  Native  silver  occurs  in  masses  and  string-like  ar- 
borescences,  penetrating  rocks,  and  is  found  in  igneous  rocks 
and  in  sedimentary  strata,  in  the  vicinity  of  dikes  of  trap 
and  porphyry. 

The  mines  of  Norway,  at  Kongsberg,  formerly  afforded 
magnificent  specimens  of,  native  silver,  but  they  are  now 
mostly  under  water.  One  specimen  from  this  locality,  at 
Copenhagen,  weighs  five  hundred  pounds.  Other  European 
localities  are  in  Saxony,  Bohemia,  the  Hartz,  Hungary, 
Dauphiny.  Peru  and  Mexico  also  afford  native  silver.  A 
Mexican  specimen  from  Batopilas,  weighed  when  obtained, 
400  pounds;  and  one  from  Southern  Peru,  (mines  of  Huan- 
tajaya,)  weighed  over  8  cwt.  In  the  United  States,  elegant 
specimens  are  associated  with  the  native  copper  of  Lake  Su- 
perior. The  silver  generally  penetrates  the  copper  in  masses 
and  strings,  and  is  very  nearly  pure,  notwithstanding  the 
copper  about  it. 

Much  of  the  galena  of  the  west  contains  a  very  small  per 
centage  of  silver,  and  that  of  Monroe,  Conn.,  yields  nearly  3 
per  cent. 

Native  silver  has  also  been  observed  near  the  Sing  Sing 
state  prison  ;  at  the  Bridgewater  copper  mines,  N.  J. ;  and 
in  handsome  specimens  at  King's  mine,  Davidson  county, 
North  Carolina. 

Uses.  The  uses  of  silver  are,  for  the  manufacture  of  va- 
rious articles  of  luxury,  for  plating  other  metals,  for  philo- 
sophical instruments,  for  coinage,  and  also  various  purposes 
in  the  arts.  For  coins,  it  is  alloyed  in  this  country  with 
copper,  and  is  thus  rendered  harder  and  more  durable  ;  1000 
parts  of  the  coin  contains  100  parts  of  copper.  When  this 
alloy  is  boiled  with  a  solution  of  cream  of  tartar  and  sea- 
salt,  or  scrubbed  with  water  of  ammonia,  the  superficial 

How  is  native  silver  distinguished  ?  How  does  it  occur  and  in  what 
rocks  1  Where  does  silver  occur  in  the  U.  States,  and  how  1  What 
are  the  uses  of  silver  1 


•SILVEH   DEES.  321 


pnrticles  of  copper  are  removed,  and  a  surface  of  fine  silver 
is  left.  Silver  is  much  less  malleable  than  gold,  and  can- 
not be  beaten  Into  unbroken  leaves  less  than  160,000th 
part  of  an  inch  thick. 

In  expressing  in  the  arts  the  purity  of  silver,  if  absolutely 
pure,  it  is  said  to  be  silver  of  12  pennyweights  ;  if  it  con- 
tain y1^  of  its  weight  of  alloy  it  is  caHed  silver  of  11  penny- 
weights ;  if  2-12ths  be  fclloy,  it  is  called  silver  of  10  penny- 
weights, and  so  on. 

VITREOUS  sii.yER. — Sulpkuret  of  Silver*. 

Monotnetric.  In  dodecahedrons  more  or  less  modified. 
Fig.  -22a,  page  30,  and  *Jso  t>ther  modifications.  Cleavage 
sometimes  apparent  parallel  to  the  faces  of 
4he  dodecahedron.  Also  reticulated  and  mas- 
sive. 

Luster  metafile.  C^lor  tmd  streak  black- 
ish lead-gray ;  streak  shining.  Brittle.  H  = 
2—2-5.  Gr=7'19— 7-4. 

Composition:  when  pure,  silver  87'04,  sulphur  12'96L 
Before  the  blowjApe  it  intumesces,  gives  off  «.n  odor  of  sul- 
phur, and  finally  affords  a  :gk>bale  of  silver.  Soluble  in  di- 
lute nitric  acid. 

Dif.  Resembles  some  ores  of  copper  and  lead,  and  other 
ores  of  silver,  but  is  distinguished  as  a  sulphuret  by  giving 
the  odor  -of  sulphur  before  the  blowpipe,  and  as  an  ore  of 
silver  by  affording  a  globule  of  this  metal,  by  heat  alone, 
Its  specific  gravity  is  much  higher  than  any  copper  ores. 

Obs.  This  important  ore  of  silver  occurs  in  Europe, 
principally  at  Annaberg,  Joachiaistahl,  and  other  mines  of 
the  Erzgebirge  ;  at  Sdhemmtz,  and  Kremnitz,  in  Hungary, 
and  at  Freiberg  in  Saxony.  It  is  a  common  ore  at  the  Mex- 
ican silver  mines,  and  also  in  the  mines  of  South  America. 

A  mass  of  sulphuret  of  silver,  is  stated  by  Troost,  to  have 
feeen  found  in  Sparta,  Tennessee.  It  also  occurs  with  na- 
tive silver  and  copper  in  Northern  Michigan. 

Uses.  This  is  a  common  and  highly  valuable  ore  of  sil- 
ver. 

Besides  this  salphuret  of  silver  there  are  two  o&ers,  which  contain 
abo  sulphuret  of  iron  or  coffer. 

What  is  the  appearance  of  vitreous  silver  ?  What  is  its  composition! 
What  is  ita  value  ?  How  io  dt  distinguished  2 


322  METALS. 

Stromeyerite.  This  is  a  steel-gray  sulphuret  of  silver  and  copper, 
containing  52  per  cent,  of  silver.  Gr=6'26.  Before  the  blowpipe  il 
fuses  and  gives  an  odor  of  sulphur  ;  but  a  silver  globule  is  not  obtained 
except  by  cupellation  with  lead.  A  solution  in  nitric  acid  covers  a 
plate  of  iron  with  copper,  and  a  plate  of  copper  with  silver  indicating 
the  copper  and  silver  present.  From  Peru,  Siberia,  and  Europe. 

Sternbergite.  A  sulphuret  of  silver  and  iron  containing  33  per  cent, 
of  silver.  It  is  a  highly  foliated  ore  resembling  graphite,  and  like  it 
leaving  a  tracing  on  paper ;  the  thin  Iamina3  are  flexible  and  may  be 
smoothed  out  by  the  nail.  Luster  metallic,  color  pinchbeck  brown. 
Streak  black.  It  affords  the  odor  of  sulphur  and  a  globule  covered 
with  silver  on  charcoal,  before  the  bio  wipe.  With  borax  a  globule  of 
silver  is  obtained.  From  Joachimstahl,  in  Bohemia. 

BRITTLE  SILVER  ORE. — Sulphuret  of  Silver  and  Antimony* 

Trimetric.  In  modified  right  rhombic  prisms.  M  :  M=^ 
115°  39'.  No  perfect  cleavage.  Often  in  compound  crys- 
tals. Also  massive. 

Luster  metallic  ;  streak  and  color  iron-black.  H  =  2 — 2*5. 
Gr=6-27. 

Composition  :  Sulphur  16*4,  antimony  14*7,  silver  68*5, 
copper  0'6.  Before  the  blowpipe  it  gives  an  odor  of  sulphur 
and  also  fumes  of  antimony,  and  yields  a  dark  metallic  glob- 
ule from  which  silver  may  be  obtained  by  the  addition  of 
soda.  Soluble  in  dilute  nitric  acid,  and  the  solution  indi- 
cates the  presence  of  silver  by  silvering  a  plate  of  copper. 

Dif.  The  black  color  of  this  ore  distinguishes  it  from 
the  preceding  ;  and  more  decidedly  the  fumes  of  antimony 
given  off  before  the  blowpipe.  By  the  trial  with  nitric  acid 
as  well  as  by  soda  and  the  blowpipe,  it  is  ascertained  to  be 
an  ore  of  silver. 

Obs.  It  occurs  with  other  silver  ores  at  Freiberg,  Schnee- 
berg,  and  Johanngeorgenstadt,  in  Saxony  ;  also  in  Bohe- 
mia, and  Hungary.  It  is  an  abundant  ore  in  Chili,  Peru, 
and  Mexico.  It  is  sometimes  called  black  silver. 

An  antimonial  sulphuret  of  silver  is  said  to  occur  with 
native  silver  and  native  copper,  at  the  copper  mines  in 
Michigan. 

Uses.  This  is  a  very  important  ore  far  obtaining  silver, 
especially  at  the  South  American  mines. 

Besides  this  there  are  other  anthnonial,  and  also  arsenical  and  sele- 
niferous  ores  of  silver. 

What  is  the  composition  of  brittle  silver  cxre  1  its  color  and  appear- 
ance ?  For  what  is  it  valued  I 


SILVER    ORES.  323 

Antimonial  Silver,  consists  simply  of  silver  and  antimony,  ,(84  parts 
to  16,)  and  has  nearly  a  tin-white  color.  Gr=9'4 — 9'8.  Before  the 
blowpipe  gray  fumes  of  antimony  pass  off,  leaving  finally  a  globule  of 
silver. 

Polybasite  is  near  brittle  silver  ore  in  color,  specific  gravity,  and  com- 
position, but  contains  some  arsenic  and  copper,  with  64'3  per  cent,  of 
silver.  The  crystals  are  usually  in  tabular  hexagonal  prisms,  without 
cleavage.  From  Mexico  and  Peru. 

Miargyrite  is  an  antimonial  sulphuret  of  silver,  containing  but  36-5 
per  cent,  of  silver,  and  having  a  dark  cherry-red  streak,  though  iron- 
black  in  color.  Before  the  blowpipe  gives  off  fumes  of  antimony  and 
an  odor  of  sulphur  ;  and  with  soda,  a  globule  is  left,  which  finally  yields 
a  button  of  pure  silver. 

Dark  Red  Silver  Ore,  and  Light  Red  Silver  Ore,  are  two  allied  ores 
rhombohedral  in  their  crystals.  The  former  contains  silver  (59  per 
cent.,)  antimony,  and  sulphur,  and  has  a  color  varying  from  black  to 
cochineal  red,  a  metallic  adamantine  luster,  and  «  red  streak.  H=2'5. 
Gr=5-7— £-9. 

The  latter  consists  of  silver,  (64- 7  per  cent.)  arsenic,  and  sulphur. 
Its  color  and  streak  are  cochineal  red.  H=2 — 2'5.  Gr=5'4 — 
5'6.  Before  the  blowpipe  these  species  fuse  easily,  give  off  fumes,  one 
of  antimony,  the  other  of  arsenic  ;  and  finally  a  globule  of  silver  is  ob- 
tained. They  are  abundant  ores  in  Mexico,  and  occur  also  in  Saxony, 
Hungary,  and  Bohemia.  These  ores  have  been  called  ruby  silver. 

Eucairite  is  a  seleniferous  ore  of  silver  and  copper  occurring  in  black 
metallic  films.  It  gives  before  the  blowpipe  fumes  of  selenium,  having 
an  odor  like  that  of  decaying  horse-radish.  From  Sweden.  Another 
eeleniferous  ore,  from  the  Hartz,  called  selensilver,  contains  silver 
and  selenium,  with  a  little  lead,  and  crystallizes  in  cubes. 

Telluric  Silver  is  a  Russian  ore,  of  a  steel-gray  color,  containing 
silver  62*3,  and  tellurium  36'9.  Another  variety  contains  18  per  cent, 
of  gold.  Gr=8'3 — 8'8.  With  soda,  silver  is  obtained. 

Carbonate  of  Silver  is  a  rare  ore  of  an  ash-gray  color,  consisting  of 
carbonic  acid  and  oxyd  of  silver.  It  is  easily  reduced  before  the  blow- 
pipe. 


HORN    SILVER. CldoTld   of 

Monometric.  In  cubes,  with  no  distinct  cleavage.  Also 
,  massive,  and  rarely  columnar  ;  often  incrustiug. 

Color  gray,  passing  into  green  and  blue,  and  looking 
somewhat  like  horn  or  wax.  Luster  resinous,  passing  into 
adamantine.  Streak  shining.  Translucent  to  nearly  opaque. 
Cuts  like  wax  or  horn. 

Composition:  when  pure,  silver  75-3,  chlorine  24-7. 
Fuses  in  the  flame  of  a  candle,  and  emits  acrid  fumes.  Af- 
fords silver  easily  on  charcoal.  The  surface  of  a  plate  of 
iron  rubbed  with  it  is  silvered. 

Describe  horn  silver.     Of  what  does  it  consist  ? 


824 

Obs.  A  very  common  OFO  snd  extensively  worked  in  the 
mines  of  South  America  and  Mexico,  where  it  occurs  with 
native  silver.  It  also  occurs  at  the  mines  of  Saxony,  Sibe- 
ria, Norway,  the  Hartz,  and  hi  Cornwall. 

lodic  Silver.  Bromic  Silver.  Silver  also  seeurs  in  nature  anitej 
with  iodine  and  bromine.  These  rare  orfs  occur  with  the  preceding 
in  Mexico,  and  the  latter  in  Chile,  and  at  Huelgoet,  in  Brittany. 

Chenocoprolite,  (gansekothig-erz  of  the  Germans.)  Mammiilary,  of  a 
yellow  or  pale  green  color  ;  luster  resinous.  Yields  silver  and  allia* 
ceous  fumes  before  the  blowpipe,  and  is  supposed  to  be  aa  arseaate  of 
silver  and  iron. 

REMARKS  ON  SILVER  AND  ITS  OREB. 

The  ores  from  which  the  silver  of  commerce  is  mostly  obtained  are 
the  vitrcovs  silver,  brittle  or  black  silver  ore,  red  silver  ore  and  horn 
silver,  in  addition  to  native  silver.  Besides  these,  silver  is  obtained  in 
large  quantities  from  galena,  (lead  ore,)  and  from  different  ores  of  cop-* 
per  :  and  some  galenas  are  so  rich  in  silver  that  the  lead  is  neglected 
for  the  more  precious  metal.  This  metal  occurs  in  rocks  of  various 
ages,  in  gneiss,  and  allied  rocks,  in  porphyry,  trap,  sandstone,  lime- 
stone, and  shales  ;  and  the  sandstone  and  shales  may  be  as  recent  as  the 
middle  secondary,  as  is  the  case  in  Prussia,  and  probably  also  in  our 
own  Michigan  mining  region.  The  silver  ores  are  associated  often 
with  ores  of  lead,  zinc,  copper,  cobalt,  and  antimony,  and  the  usual 
gangue  is  calc  spar  or  quartz,  with  frequently  fluor  spar,  pearl  spar,  or 
heavy  spar. 

The  silver  of  South  America  is  derived  principally  from  the  horn  sil- 
ver, brittle  silver  ores,  including  aiseniuretted  silver  ore,  vitreous  silver 
ore,  and  native  silver.  Those  of  Mexico  are  of  nearly  the  same  charac- 
ter. Besides,  there  are  earthy  ores  called  colorados,  and  in  Peru  pacos, 
which  are  mostly  earthy  oxyd  of  iron,  with  a  little  disseminated  silver  ; 
they  are  found  near  the  surface  where  the  rock  has  undergone  partial 
decomposition.  The  sulphurets  of  lead,  iron,  and  copper,  of  the  mining 
regions,  generally  contain  silver,  and  are  also  worked. 

The  mines  of  Mexico  are  most  abundant  between  18°  and  24°  north 
latitude,  on  the  back  or  sides  of  the  Cordilleras  and  especially  the  west 
side  ;  and  the  principal  are  those  of  the  districts  of  Guanaxuato,  Zaca- 
tecas,  Fresnillo,  Sombrerete,  Catorce,  Oaxaca,  Pachuca,  Real  del  Monte, 
Moran,  and  Pasco.  The  veins  traverse  very  different  rocks  in  these 
regions.  The  vein  of  Guanaxuato,  the  most  productive  in  Mexico,  in- 
tersects argillaceous  and  chloritic  shale,  and  porphyry  ;  it  affords  one- 
fourth  of  all  the  Mexican  silver.  The  Valencian  mine  is  the  richest  in 
Guanaxuato,  and  has  yielded  for  many  years,  from  one  to  two  millions 
of  dollars  annually.  In  the  district  of  Zacatecas  the  veins  are  in  gray- 


Where  is  horn  silver  a  common  ore  ?  From  what  ores  is  the  silver 
of  commerce  mostly  obtained  ?  How  do  they  occur?  What  are  the 
common  ores  of  South  America  ? 


SILVER    ORES.  325 

wacke.  In  Sombrerete  they  occur  in  limestone  ;  and  there  are  exten- 
sive veins  of  the  antimonial  sulphuret,  one  of  which  gave  in  six  months 
700,000  marcs,  (418,000  Ibs.  troy)  of  silver.  The  Pachcca,  Real  del 
Monte,  and  Moran  districts,  are  near  one  another.  Four  great  parallel 
veins  transverse  these  districts,  through  a  decomposed  porphyry.  From 
the  vein  Biscaina,  in  Real  del  Monte,  $5,000,000  were  realized  by  the 
Count  de  Regla,  in  twelve  years. 

In  South  America  the  Chilian  mines  are  on  the  western  slope  of  the 
Cordilleras,  and  are  connected  mostly  with  stratified  deposits,  of  a  shaly, 
sandstone,  or  conglomerate,  character,  or  with  their  intersections  with 
porphyries.  The  chlorids  and  native  amalgams  are  found  in  regions 
more  towards  the  coast>  while  the  su(phurets  and  antimonial  ores 
abound  nearer  the  Cordilleras.  The  mountains  north  of  the  valley  of 
Huasco  contain  the  richest  silver  mines  of  Chili.  The  mines  of  Mt. 
Chanarcillo  produces  at  the  present  time  more  than  80,000  marcs  of 
silver  per  year.  The  veins  abound  in  horn  silver,  and  begin  to  yield 
arsenio-sulphurets  at  a  depth  of  about  500  feet.  The  mines  of  Punta 
Brava,  in  Copiapo,  which  are  nearer  the  Cordilleras,  afford  the  arseni- 
uretted  ores. 

In  Peru,  the  principal  mines  are  in  the  districts  of  Pasco,  Chota,  and 
Huantaya.  Those  of  Pasco  are  15,700  feet  above  the  sea,  while  those 
of  Huantaya  are  in  a  low  desert  plain,  near  the  port  of  Yquique,  in  the 
southern  part  of  Peru.  The  ores  afforded  are  the  same  as  in  Chili. 
The  mines  of  Huantaya  are  noted  for  the  large  masses  of  native  silver 
they  have  afforded. 

The  Potosi  mines  in  Buenos  Ayres,  occur  in  a  mountain  of  argilla.- 
ceous  shale,  whose  summit  is  covered  by  a  bed  of  argillaceous  porphyry. 
The  ore  is  the  red  silver,  the  vitreous  ore  along  with  native  silver.  It  has 
been  estimated  that  they  have  afforded  since  their  discovery  $1,300,- 
000,000.  These  mines  have  diminished  in  value,  though  they  still  rank 
next  to  those  of  Guanaxuato. 

In  Europe  the  principal  mines  are  those  of  Spain,  of  Kongsberg  in 
Norway,  of  Saxony,  the  Hartz,  Austria,  and  Russia.  The  mines  of 
Kongsberg  occur  in  gneiss  and  hornblende  slate,  in  a  gangue  of  calc 
spar.  They  were  especially  rich  in  native  silver,  but  are  now  nearly 
exhausted.  The  silver  of  Spain  is  obtained  mostly  from  galena,  and 
principally  in  the  Sierra  Almagrera  in  Grenada. 

The  mines  of  Saxony  occur  mostly  in  gneiss,  in  the  vicinity  of  Frey- 
>  berg,  Ehrenfriedensdorf,  Johangeorgenstadt,  Annaberg  and  Schneeberg. 

The  ores  of  the  Hartz  are  mostly  argentiferous  copper  pyrites  and 
I  galena,  yet  the  red  silver,  vitreous  silver  ore,  brittle  silver  ore,  and  ar- 
isenical  silver,  occur,  especially  at  Andreaekreutz,  and  the  mines  of  that 
j  vicinity.  The  rock  intersected. by  the  deposits  is  mostly  an  argillace- 
i  ous  shale.  Carbonate  of  lime  is  the  usual  gangue,  though  it  is  some- 
times quartz 

In  the  Tyiol,  Austria,  sulphuret  of  silver,  argentiferous  gray  copper, 

I  and  mispickel  occur  in  a  gangue  of  quartz,  in  argillaceous  schist.     The 

j  Hungarian  mines  at  Schemmitz  and   Krenmitz,  occur  in  syenite  and 

I  hornblende  porphyry,  in  a  gangue   of  quartz,  often  with  calc  spar  or 

lieavy  spar,  and  sometimes  fluor.     The   ores  are  sulphuret  of  silver, 


Where  are  the  principal  mines  in  Europe  ? 

28 


326  IflETAtS. 

gray  copper,  galena,  blende,  pyritons  copper  and"  iron  ;  and  the  galenar, 
and  copper  ores  are  argentiferous, 

The  Russian  mines  of  Kolyvan  in  the  Altai,  and  of  Nertchinsk  in  the 
Daouria  mountains,  Siberia,  (east  of  Lake  Baikal,)  are  increasing  in 
value,  and  yield  annually  76,500  marcs  (47,800  troy  pounds)  of  silver, 
The  Daouria  mines  afford  an  argentiferous  galena  which  is  worked  for 
its  silver.  It  occurs  in  a  crystalline  limestone.  The  silver  ores  of  the? 
Altai  occur  in  silurian  schists  in  the  vicinity  of  porphyry,  which  con- 
tain besides  silver  ores,  gold,  copper,  and  lead  ares. 

In  England  argentiferous  galena  is  worked  for  ks  silver.  40,000 
tons  of  the  ore  were  reduced  in  1837,  one  half  of  which  contained  8  to 
8£  oz.  of  silver  to  the  ton  of  lead,  and  the  other  half  only  4  to  5  oz.  of 
silver, 

In  the  United  States,  the  Washington  silver  mh>e,  in  Davidson  coun- 
ty, N.  Carolina,  had  afforded  i>p  to  1845,  30,000  dollars  of  silver.  The 
native  silver  of  Michigan  is  associated  with  copper  in  trap  and  sand- 
atone.  These  mines  promise  to  be  highly  productive. 

The  silver  mines  of  the  world  hate  been  estimated  to  yield  at  the 
present  time  $20,000,000  annually. 

The  annual  product  of  the  several  countries  of  Europe  is  nearly  as 
follows ; — 

pounds  troy.  pounds  troy. 


British  Isles.  7,500 

France,  4,150 

Austria,  63,000 

Sweden  and  Norway,  13,000 

Spain,  130,000 


Saxony,  the  Hartz,  and 

other  parts  of  Germany, 
Belgium,  440 

Piedmont,  Switzerland  and 

Saxony, 


making  in  all  298,150  troy  pound's,  or  about  4,500,000  dollars  annually. 
With  the  sum  from  Russia,  about  730,000  dollars,  it  becomes  5,230,00j| 
a  year.  This  is  small  compared  with  the  amount  from  America,  which 
at  the  beginning  of  the  present  century  equalled  2,100,000  pounds,  or 
31£  millions  of  dollars,  nearly  six  timesr  the  above  sum  ;  and  it  is  prob- 
able that  these  mines  will  again  yield  this  amount  when  properly 
worked.  The  whole  sum  from  Russia,  Europe,  and  America,  makes 
nearly  2,000,000  pounds  avoirdupois. 

The  common  modes  of  reducing  silver  ares  in  the  large  way  arc  two  ; 
by  amalgamation,  and  by  smelting.  Both  mercury  and  lead  have  a 
strong  affinity  for  silver,  and  these  reducing  processes  are  based  on  this 
fact.  In  amalgamation,  the  silver  ore  is  brought  to  the  state  of  a  chlo- 
rid  by  a  mixture  of  the  powdered  ore  (or  "  schlich,")  with  about  ten  per 
cent,  of  common  salt ;  the  chlorid  is  reduced  by  means  of  salts  or  sul- 
phurets  of  iron,  or  metallic  iron  in  filings,  and  at  the  same  time  mer- 
cury which  has  been  added,  combines  with  the  liberated  silver,  and  thus 
separates  it  in  the  condition  of  an  amalgam,  (a  compound  of  mercury 
and  silver.)  The  mixture  of  salt  and  "schlich"  requires  several  days  to 
become  complete.  Heat  is  employed  at  the  Saxon  mines,  but  not  at 
those  of  Mexico,  where  the  climate  is  tropical.  After  the  mercury  is 
put  in,  (6  or  8  parts  to  1  of  silver,)  the  mixture  is  kept  in  constant  agi- 

Where  are  the  Russian  mines?  What  is  the  yield  of  the  silver 
mines  of  the  world]  What  was  afforded  by  South  America  at  the  be- 
ginning of  this  century  ?  Describe  the  process  of  amalgamation. 


•SILVER    ORES. 


327 


tafian  rnitil  the  process  is  finished.  In  the  best  arrangements,  as  ia 
Saxony,  this  agitation  is  performed  in  revolving  barrels,  and  the  result 
is  accomplished  in  ^i  few  hours ;  but  in  Mexico  it  is  effected  by  the 
treading  of  mules  or  oxen,  and  requires  two  or  three  weeks  or  more. 
The  amalgam,  separated  from  the  muddy  mass,  by  a  current  of  water 
or  washing,  is  then  filtered  of  the  excess  of  mercury  ;  as  -a  last  step  it  is 
subjected  to  heat  in  a  distilling  furnace,  by  which  the  silver  is  left  be- 
liind,  the  mercury  passing  off  in^.  state  of  vapor  to-be  condensed  in  a 
condensing  chamber  or  receptacle.  The  Joss  -of  mercury  by  the  pro- 
cess is  often  large. 

In  case  of  the  ordinary  sulphupeis  and  arseniiireis  of  silver,  or  the 
chlorid,  in  Mexico  and  .South  America,  the  poorer  ores  are  first  fused 
with  a  flux,  and  the  result,  .(.called  the  ".matt")  is  then  roasted  to  expel 
the  sulphury  afterwards  it  is  mixed  with  -better  ores,  again  fused,  and 
on  cooling,  again  roasted.  This  fusion  and  roasting  is  again  repeated 
with  the  best  ores.  Tiie  result  from  this  fusion  is  next  mixed  thorough- 
ly with  melted  lead  ;  the  lead  separates  the  silver ;  and  the  impurities 
which  float  on  fhe  surface,  are  removed  in  plates  as  a  -crust  cools,  to  be 
tgain  melted  with  new  ores,  as  the  slag  is  apt  to  contain  some  of  the 
•River. 

When  the  argentiferous  galena  is  the  ore,  it  is  reduced  by  roasting  ia 
%  reverberatory  furnace  in  the  ordinary  way  for  lead  OK  ;  the  resulting 
»ead  contains  aleo  the  silver. 

The  accompanying  sketch  represents  the  essential  characters  of  a 
teverberatory  furnace.  It  is  a  transverse  section.  A  is  tae  .grate  on 
which  the  fire  is  made, 
«nd  from  which  the  flame 
proceeds  through  the  hor- 
izontal chamber  or  gen- 
eral cavity  of  the  furnace, 
^usually  very  low,)  to 
fhe  flue  at  e.  b  is  the 
sole  of  the  hearth,  for  re- 
receiving  the  ore  or  as- 
say, having  an  elliptical  or  circular  form  according  to  the  shape  of 
fhe  furnace;  jc  is  the  fife  bridge,  separating  the  fire  from  the  sole; 
<i  is  the  arched  roof.  The  flame  plays  horizontally  over  the  charge  of 
ore,  and  as  the  air  may  be  made  to  pass  freely  with  it,  we  may  have  ia 
«uch  a  /amaee«  combined  effect  derived  from  the  heat  and  the  pres- 
ence of  the  atmosphere  ;  the  ore,  or  its  metal,  if  capable  of  uniting  with 
the  oxygen  of  the  atmo^>here,  may  be  oxydated  by  the  process,  pre- 
cisely as  in  -the  outer  or  oxydating  flame  of  the  blowpipe.  In  an  or- 
dinary blast  furnace,  (page  233,)  the  ope  and  its  flux  are  confined  from 
the  atmosphere,  (except  the  .air  that  -enters  wkh  the  blast,)  and  the  re- 
sult is  the  reduction  x>f  an  ore  or  its  deoxydation,  as  in  -the  inner  or  re- 
ducing flanae  of  the  blowpipe.  This  latter  effect  may  in  many  cases 
*be  obtained  also  with  a  reverberatory  furnace,  when  the  atmosphere  is 
excluded  except  what  ie  essential  to  feeding  the  fire. 

In  the  reverberatory  furnace,  there  is  a  small  door  near  the  fire-grate, 
r,  for  putting  in  fuel.     There  is  also  an  opening  either  at  top,  or  on  the 


Describe  .a  reyejberato/y  fumaae- 


328  METALS. 

side,  for  introducing  the  charge  ;  also  there  may  be  one  or  .nore  doors 
on  each  side  for  working  the  charge  while  exposed  to  the  heat.  There 
may  also  be  a  tap  hole  for  drawing  off  the  reduced  metal  into  one  or 
more  pots  attached  for  the  purpose  ;  another  in  some  cases-  for  the  es- 
cape of  slag  as  in  cupellation,  and  where  there  is  a  vaporizabfe  ingre- 
dient to  be  condensed,  one  or  two  flues  leading  to  a  condensing  cham- 
ber. In  large  establishments  several  of  these  reverberatory  furnaces 
connect  with  a  single  chimney.  They  are  actually  like  large  elliptical 
or  circular  ovens,  of  brick  or  stone,  communicating  with  a  common 
flue. 

In  reverberatory  furnaces  adapted  lor  melting  metals,  the  hearth  is 
a  gently  inclined  plane,  sloping  to  a  spot  towards  one  end,  in  order  that 
the  fused  metal  may  flow  down  together  and  be  convenient  for  drawing 
off.  For  many  other  purposes,  the  sale  is  flat,  and  the  depth  is  greater 
than  in  the  above  figure. 

To  separate  the  silver  from  the  lead,  the  lead  is  heated  in  a  reverbe- 
ratory furnace,  the  hearth  of  which  is  covered  with  wood  ashes  and 
clay,  so  as  to  give  it  the  nature  of  a  cupel.  The  air  received  through 
an  aperture  on  one  side,  passes  over  the  metal  in  fusion,  in  a  constant 
current,  oxydizing  it  and  changing  it  to  litharge,  which  is  from  time  to 
time  drawn  out ;  finally  the  lead  is  thus  removed,  and  the  silver  remains 
nearly  pure.  The  completion  of  the  process  is  known  by  the  metal  be- 
coming brilliant.  It  is  again  subjected  to  another  similar  operation,  and 
thus  rendered  quite  pure.  The  litharge  from  the  latter  part  of  the  pro- 
cess is  also  subjected  to  another  operation  for  the  silver  it  usually  con- 
tains. 

According  to  Pattinson's  new  process,  adopted  in  England,  the  silver 
is  separated  by  melting  the  lead,  and*  as  it  begins  to  cool,  straining  ouil 
the  crystals  with  an  iron  strainer.  The  portion  left  behind  contains 
nearly  all  the  silver.  This  is  several  times  repeated,  each  time  the  re- 
maining lead  becoming  richer  in  silver.  This  is  then  cupelled.  An 
ore  containing  only  3  ounces  of  silver  to  the  ton  of  lead,  (or  but  1- 
10,000th  part,)  may  thus  be  profitably  worked,  and  with  little  loss  of 
lead. 

When  the  ore  containing  silver  is  a  copper  ore,  as  is  often  the  case 
with  gray  copper  ore,  the  calcined  ore  is  mixed  with  lead  or  lead  ore, 
and  fused  and  calcined,  and  the  resulting  products  are  either  liquated  to 
sweat  out  the  silver  or  cupelled.  In  liquation,  the  copper  is  run  into 
iDJgs,  (called  liquation  cakes,)  and  kept  above  a  red  heat  for  two  or  three 
days  ;  the  lead  first  melts  and  flows  in  drops  into  cast  iron  troughs,  car- 
rying with  it  the  silver,  which  is  afterwards  obtained  by  cupelling. 
The  copper  still  contains  some  of  the  lead. 

In  trials  by  cupellation,  a  piece  of  lead  of  known  weight  is  placed  in 
a  cup  of  bone-ashes,  and  this  is  subjected  to  heat  in  a  small  air  cham- 
ber or  oven,  and  placed  in  a  furnace  so  that  the  air  shall  have  free  ac- 
cess. The  lead  is  oxydized,  and  the  oxyd  sinks  into  the  cupel,  leaving 
a  globule  of  silver  behind.  The  globule  being  then  weighed,  and  com- 
pared with  the  weight  of  lead,  the  proportion  of  silver  is  aseenained. 
Silver  may  thus  be  found  in.  almost  any  specimen  of  the  lead  of  com- 

What  is  the  process  of  amalgamation  with  an  argentiferous  lead  are  ? 
"What  is  the  mode  of  trial  by  cupellation  I 


SIITER    ORES,  32$ 

,  howrver  small  the  .proportion.  The  weight  of  the  globule,  es- 
pecially when  qnite  minute,  may  be  afeo  ascertained  by  measurement, 
according  to  a  scale  given  by  Prof.  W.  W.  Mather,  in  the  American 
Journal  of  Science,  volume  iii,  second  series,  page  414.  Much  that 
has  been  mentioned  in  fhe  preceding  pages  on  the  American  mines  of 
silver,  has  been  derived  from  au  article  by  Prof.  Mather,  in  volume 
xxiv,  of  ihe  same  Journal. 

Other  modes  of  reducing  silver  eres  without  quicksilver,  have  been 
proposed.  According  to  one,  the  ore  is  calcined  with  common  salt,  as 
in  Mexico,  and  converted  thus  Xo  a  chlorid.  It  is  then  removed  to  some 
proper  vessel,  and  a  hot  solution  of  salt  poured  over  it ;  this  takes  up 
the  chlorid  of  silver  and  holds  it  in  solution.  The  liquid  is  transferred 
lo  another  vessel,  and  by  means  of  metallic  copper  the  silver  is  de- 
posited. 

Another  process  consists  i«  roasting  the  sulphurets  «nd  converting 
them  in  a  reverberatory  furnace  to  sulphates ;  then  by  boiling  watec, 
•dissolving  the  sulphates  in  a  proper  vessel,  and  finally  precipitating  as 
above  by  copper.  This  process  requires  the  presence  of  a  good  deal  of 
sulphur,  and  is  the  best  when  there  is  much  iron  and  copper  pyrites 
present. 

In  the  assay  to  separate  copper  from  silver,  the  alloy  is  dissolved  in 
nitric  acid,  and  the  silver  precipitated  in  the  state  of  a  chlorid  by  com- 
mon salt.  The  amount  of  -silver  may  then  be  ascertained  by  weighing 
the  precipitated  chlorid,  and  observing  that  75'33  per  cent,  of  the  chlo- 
rid is  pure  silver. 

SUPPLEMENT  TO  THE  DESCRIPTION  OF  MINERALS. 

Bamlite.  White  or  grayish-white ;  columnar.  H=6.  Gr=2-98. 
Contains  silica  56-9,  alumina,  42,  and  1  per  cent,  of  peroxyd  of  iron. 
From  Norway. 

Berzeline.  In  minute  white  crystals  from  the  Roman  states.  Ge- 
latinizes. 

Beudantite.  A  black  mineral,  with  resinous  luster :  crystals  rhom- 
bohedral;  R:  R=92°  30*.  Contains  oxyds  of  lead  and  iron.  From 
Horhausen  on  the  Rhine. 

Castor.  A  colorless  transparent,  feldspar-like  mineral,  from  Elba, 
H=6'5.  Gr=2'38 — 2'4.  Angle  between  two  distinct  cleavages, 
128£°  or  129°.  Contains  silica  78-0,  alumina  18'9,  oxyds  of  iron  and 
manganese  1*6,  lithia,  potash,  and  soda,  2*8. 

Cereolite.  A  hydro-silicate  of  magnesia  and  alumina,  occurring  in 
globules  in  wacke,  and  resulting  from  its  decomposition. 

Christianite.  This  is  one  of  the  names  of  anorthite.  It  has  also 
been  recently  applied  to  a  mineral  near  Phillipsite,  from  Iceland,  with 
which  the  Marburg  phillipsite  is  said  to  be  identical. 

Danburite.  Honey-yellow,  vitreous.  A  hydrous  silicate  of  lime. 
A  doubtful  species. 

Gilbertite.  In  aggregated  plates  ;  white  or  yellowish ;  silky ;  trans- 
lucent. H=2-75.  Gr=2-65.  Composition:  silica  45'2,  alumina 
40-1,  lime  4'2,  magnesia  1-9,  peroxyd  of  iron  2'4,  water  4  25.  With 
fluor  spar,  in  Cornwall. 

Hydrotalcite.     A  steatitic  mineral  from  Snarum,  consisting  of  mag- 
nesia, alumina,  peroxyd  of  iron,  carbonic  acid,  and  water. 
28* 


330  SUPPLEMENT. 

KalipJiite.  Fragile,  feathery,  resinous,  opaque;  powder  lecfcfisfo- 
brown.  G=2  8.  Contains  oxyds  ©f  iron,  manganese,  and  zinc,  with 
water  and  silica. 

Liebigite.  Carbonate  of  uranium  and  lime,  in  mammillary  concre- 
tions of  an  apple-green  color.  From  near  Adrianople,  Turkey. 

Medjidite.  Sulphate  of  uranium  and  lime,  of  a  dark  amber  color. 
From  near  Adrianople,  Turkey. 

Monticellite.  In  small  prismatic  crystals  at  Vesuvius.  M  :  M== 
132°  34'.  Color  yellowish;  transparent.  Fuses  with  difficulty.  Gela- 
tinizes. Near  chrysolite. 

Ozarkite.  Massive,  of  a  white  or  reddish- white  color,  and  feeble  vi- 
treous to  resinous  luster.  H=4'5..  Gr=2'75.  Very  easily  fusible.  Asso- 
ciated with  elseolite  in  veins  and  small  masses,  in  the  Ozark  mountains, 
Arkansas. 

Pigotite.  Massive  ;  brownish  ;  powder  yellow.  Insoluble.  Burns 
with  difficulty.  Consists  of  an  organic  acid,  called  mudescous  acid, 
combined  with  alumina. 

Pollux.  Resembles  castor,  but  has  only  traces  ©f  cleavage.  Gr= 
2-85 — 2-9.  Contains  46  per  cent,  of  silica,  165  of  potash,  14"5  of  aoda, 
and  is  hydrous. 

Porcelain  spar.  In  square  prisms  and  allied  to  Scapolite.  In  gran- 
ite in  Bayern. 

Praseolite.  Imperfectly  crystallized.  Color  light  or  dark  green*, 
with  a  weak  luster,  clear  green  streak.  H=3'5.  Gr=2'75.  Frac- 
ture splintery.  Composition :  silica  40'9,  alumina  28*8,  protoxyd  of 
iron  7'0,  magnesia  13'7,  water  7'4.  From  Brevig,  Norway,  in  granite. 

Saussurite.  A  tough,  massive  mineral,  cleavable  and  affording  a 
prism  of  124°.  Color  white,  greenish,  or  grayish.  Luster  pearly, 
sometimes  resinous.  Composition :  silica  49,  alumina  24,  lime  10  5, 
magnesia  3'75,  peroxyd  of  iron  6'5,  soda  5'5.  Fuses  with  great  diffi- 
culty before  the  blowpipe.  Resembles  nephrite,  but  contains  largely 
of  alumina  with  but  little  magnesia.  It  constitutes  in  part  the  rocks 
called  gabbro  and  euphotide,  and  comes  from  the  borders  of  the  lake  of 
Geneva,  where  it  was  first  observed  by  Saussure  Senior.  It  is  also 
found  in  Corsica,  Greenland,  and  Madras. 

Stroganowite.  Near  scapolite.  Said  to  have  the  constitution  of 
scapolite,  with  the  addition  of  carbonate  of  lime. 

Tachylite.  A  doubtful  glassy  black  mineral,  resembling  obsidian, 
found  on  trap.  Consists  of  silica  and  alumina,  with  lime,  potash,  soda, 
and  protoxyd  of  iron. 

Tautolite.  Velvet  black  and  vitreous.  H=6"5 — 7.  Gr=3'8G5. 
A  siliceous  mineral,  containing  oxyd  of  iron,  besides  magnesia  and 
alumina.  Occurs  in  volcanic  feldspathic  rocks. 

Botryogen.  A  hydrous  sulphate  of  iron  and  magnesia,  of  a  deep 
hyacinth-red  color.  From  Fahlun,  Sweden. 

Forms  of  Gems. — Gems  are  cut  either  by  cleaving,  by  sawing  with 
a  wire  armed  with  diamond  dust,  or  by  grinding.  Some  remarks  on  the 
cutting  of  the  diamond  are  given  on  page  83.  The  harder  stones,  as 
the  sapphire  and  topaz,  are  cut  on  a  copper  wheel  with  diamond  powder 
soaked  with  olive  oil,  and  are  afterwards  polished  with  tripoli.  For 
other  gems,  less  hard,  a  lead  wheel  with  emery  and  water  is  first  used, 
and  then  a  tin  or  zinc  wheel  with  putty  of  tin  or  rotten  stone  and  water. 


SUPPLEMENT. 


The  following  are  some  of  the  common  forms.  It  will  be  remem- 
bered that  the  upper  truncated  pyramid  is  called  the  table,  the  lower  part 
or  pyramid,  the  collet,  and  the  line  of  junction  between  the  two  pans, 
the  girdle.  Figures  1  and  2  represent  the  brilliant,  the  best  form  of"  the 
diamond,  used  also  for  other  stones,  as  well  as  pastes.  Figs.  3  and  4 
are  views  of  a  variety  of  the  rose  diamond.  Figs.  5  and  6  the  same  of 
an  emerald.  The  cut  in  steps  is  called  the  pavilion  cut.  Fig.  1  is  an 
1  23 


xAx 
/MVlyK 


tipper  view  of  a  mode  of  cutting  the  sapphire.  A  side  view  would  be 
nearly  like  figure  6,  except  that  the  collet  is -more  like  that  of  figure  8. 
Fig.  8  represents  a  side  view  of  an  oriental  topa$.  The  table  has  the 
brilliant  cut,  like  figs.  1  and  2.  Figure  9  represents  a  Bohemian  gar- 
net, which  is  made  thin  because  its  color  is  deep.  The  common  topaz 
is  cut  like  figure  8  ;  often  also  like  figure  9  but  much  thicker,  and  fre- 
quentl/  having  the  table  bordered  by  two  or  more  rows  of  triangular 
facets.  Figure  10  is  a  very  simple  table.  Figures  11  and  12  represent 
the  form  "  en  cabochon"  given  the  opal;  and  figures  12  and  13,  "en 
cabochon"  with  facets,  a  mode  of  cutting  the  chrysoberyl. 


332  ROCKS. 


CHAP.  VII.— ROCKS  OR  MINERAL  AGGREGATES. 

General  Nature  of  Rocks.  In  the  early  part  of  this  vol- 
ume it  is  stated  that  the  rocks  of  the  globe  are  mineral  in 
their  nature,  and  consist  either  of  a  single  mineral  in  a  mas* 
sive  state,  or  of  intimate  combinations  of  different  minerals. 
Limestone,  when  pure,  is  a  single  mineral, — it  is  the  spe- 
cies calcite  or  carbonate  of  lime  ;  common  granite  is  a  com- 
pound or  aggregate  of  three  minerals,  quartz,  feldspar,  and 
mica.  Sandstones  may  consist  of  grains  of  quartz  alone,  like 
the  sands  of  many  sea-coasts,  being  such  a  rock  as  these 
sands  would  make  if  agglutinated ;  it  is  common  to  find  along 
with  the  quartz,  grains  of  feldspar,  and  sometimes  mica. 
Clay  slates  consist  of  quartz  and  feldspar  or  clay,  with  some- 
times mica,  all  so  finely  comminuted,  that  often  the  grains  can- 
not be  observed.  Conglomerates  or  puddingstones,  may  be 
aggregates  of  pebbles  of  any  kind :  of  granite  pebbles,  of 
quartz  pebbles,  of  limestone  pebbles,  or  of  mixtures  of  differ- 
ent kinds,  cemented  together  by  some  cementing  material, 
such  as  silica,  oxyd  of  iron,  or  carbonate  of  lime. 

Texture  or  structure  of  Rocks. — Rocks  differ  also  in  tex- 
ture. In  some,  as  granite,  or  syenite,  the  texture  is  crys- 
talline :  that  is,  the  grains  are  more  or  less  angular,  and 
show  faces  of  cleavage  ;  the  aggregation  was  the  result 
of  a  cotemporaneous  crystallization  of  the  several  ingredi- 
ents. Common  statuary  or  white  building  marble,  consists 
of  angular  grains,  aad  is  crystalline  in  the  same  manner. 
But  a  pudding-stone  is  evidently  not  a  result  of  crystalliza- 
tion ;  it  consists  only  of  adhering  pebbles  of  other  rocks  with 
a  cementing  material  which  is  often  not  apparent.  Sand- 
stones also  are  an  agglutination  of  grains  of  sand, — just  such 
rocks  as  would  be  made  from  ordinary  sand  by  compacting 
it  together  ;  and  clay  slates  are  often  just  what  would  result 
from  solidifying  a  bed  of  clay.  There  are  therefore  crystal- 
line and  uncrystallitie  rocks.  It  should  be  remembered, 
however,  that  in  each  kind  of  rock  the  grains  themselves 
are  crystalline,  as  all  solid  matter  becomes  solid  by  crystal, 
lization.  But  the  former  kind  is  a  crystalline  aggregation 
of  grains,  the  latter  a  mechanical  aggregation. 

In  crystalline  rocks  it  is  not  always  possible  to  distinguish 
the  grains,  as  they  may  be  so  minute,  or  the  rock  so  com- 


ROCKS.  333 

pact,  that  they  are  not  visible.  Much  of  the  crystalline  rock 
called  basalt  is  thus  compact. 

Positions,  or  modes  of  occurrence  of  Rocks.  A  great  part 
of  the  rocks  of  the  earth's  surface  constitute  extensive  beds 
or  layers,  lying  one  above  the  other,  and  varying  in  thick- 
ness from  a  fraction  of  an  inch  to  many  scores  of  yards. 
There  are  compact  limestones,  beds  of  sandstone,  and  shales 
or  clay  slates,  in  many  and  very  various  alternations.  In 
some  regions,  certain  of  these  rocks,  or  certain  parts  of  the 
series,  may  extend  over  large  areas  or  underlie  a  whole 
country,  while  others  are  wholly  wanting  or  present  only  in 
thin  beds.  The  irregularities  in  their  geographical  ar- 
rangement and  in  the  order  of  superposition  are  very  nume- 
rous, and  it  is  one  object  of  geology  to  discover  order  amid 
the  apparent  want  of  system.  Thus  in  Pennsylvania,  over  a 
considerable  part  of  the  state,  there  are  sandstones,  shales, 
and  limestones,  connected  with  beds  of  coal.  In  New  York 
there  are  other  sandstones,  shales,  and  limestones,  without 
coal ;  and  the  geologist  ascertains  at  once  by  his  investiga- 
tions, (as  was  observed  in  the  remarks  on  coal,)  that  no  coal 
can  be  expected  to  be  found  in  New  York.  These  rocks 
contain  each  its  own  peculiar  organic  remains,  and  these 
are  one  source  of  the  confident  decision  of  the  geologist. 
The  stratified  rocks  bear  evidence  in  every  part — in  their  reg- 
ular layers,  their  worn  sand  or  pebbles,  and  their  fossils, — 
that  they  are  the  result  of  gradual  accumulations  beneath  wa- 
ter, marine  or  fresh,  or  on  the  shores  of  seas,  lakes  or 
rivers. 

Besides  the  slratified  rocks  alluded  to,  there  are  others 
which,  like  the  ejections  from  a  volcano,  or  an  igneous  vent, 
form  beds,  or  break  through  other  strata  and  fill  fissures  often 
many  miles  in  length.  The  rock  filling  such  fissures,  is 
called  a  dike.  Such  are  the  trap  dikes  of  New  England 
and  elsewhere  ;  they  are  fissures  filled  by  trap.  Porphyry 
dikes,  and  many  of  the  veins  in  rocks,  are  of  the  same  kind. 
Similar  rocks  may  also  occur  as  extensive  layers ;  for 
the  lavas  of  a  single  volcanic  eruption  are  sometimes  con- 
tinuous for  40  miles.  They  may  appear  underlying  a  wide 
region  of  country,  like  granite. 

The  stratified  rocks,  or  such  as  consist  of  material  in  reg. 
ular  layers,  are  of  two  kinds.  The  worn  grains  of  which 
they  are  made  are  sometimes  distinct,  and  the  remains  of 
shells  farther  indicate  that  they  are  the  result  of  gradual  accu. 


334  ROCKS. 

mulation.  But  others,  or  even  certain  parts  of  beds  that 
elsewhere  contain  these  indications,  have  a  crystalline  tex- 
ture. A  limestone  bed  may  be  compact  in  one  part,  and 
granular  or  crystalline,  like  statuary  marble,  in  another. 
Here  is  an  effect  of  heat  on  a  portion  of  the  bed ;  heat, 
which  has  acted  since  the  rock  was  deposited.  Other  rocks, 
such  as  mica  slate,  gneiss,  and  probably  some  granites,  have 
thus  been  crystallized. 

In  these  few  general  remarks  on  the  structure  of  the  globe, 
we  have  distinguished  the  following  general  facts  : 

1.  The  great  variety  of  alternations  of  sandstone,  conglo- 
merates, clay  shale,  and  limestones. 

2.  The  existence  of  igneous  rocks  in  beds  and  intersect- 
ing dikes  or  veins. 

3.  The  mechanical  structure  of  sandstone,  conglomerate, 
and  shales. 

4.  The  crystalline  character  of  igneous  rocks. 

5.  The  crystalline  character  of  many  stratified  or  sedi- 
mentary rocks,  arising  from  the  action  of  heat  upon  the  beds 
of  rock  themselves,  after  they  were  first  formed. 

We  follow  this  comprehensive  survey  of  the  arrangement 
and  general  nature  of  rocks,  with  descriptions  of  the  more 
prominent  varieties  and  a  mention  of  their  applications  in 
the  arts.* 


*  One  of  the  most  important  uses  of  stone  is  for  architectural  pur- 
poses. The  character  of  the  material  depends  not  only  upon  its  dura- 
bility, but  also  its  contraction  or  expansion  from  changes  of  tempera- 
ture. This  latter  cause  occasions  fractures  or  the  opening  of  seams, 
and  produces  in  cold  climates  serious  injuries  to  structures.  The  fol- 
lowing table,  by  Mr.  A.  J.  Adie,  gives  the  rate  of  expansion  in  length 
tor  different  materials,  for  a  change  of  temperature  of  180°  F. — Proc. 
Boy.  Soc.  Edinb.,  i,  95,  1835. 

Granite,  -0008968— -0007894 

Sicilian  white  marble,  -00110411 

Carrara  marble,  -0006539 

Black  marble,  from  Gal  way,  Ireland,  -00044519 

Sandstone,  (Craigleith  quarry,  Scotland,)     -0011743 

Siate,  Penryhn  quarry,  Wales,  -0010376 

Greenstone,  -0008089 

Best  brick,  -0005502 

Fire  brick,  -0004928 

Cast  iron,  -001 14676—--001 102166 

Red  of  wedgewood  ware,  -00045294 


335 


GRANITE.       SYENITE. 

Granite  consists  of  the  three  minerals,  quartz,  feldspar, 
and  mica.  It  has  a  crystalline  granular  structure,  and  usual- 
ly a  grayish-white,  gray,  or  flesh-red  color,  the  shade  vary- 
ing with  the  color  of  the  constituent  minerals.  When  it 
contains  hornblende  in  place  of  mica,  it  is  called  syenite ; 
hornblende  resembles  mica  in  these  -rocks  but  the  laminae 
separate  much  less  easily  and  are  brittle. 

Granite  is  said  to  be  micaceous,  feldspathic,  or  quartzose, 
according  as  the  mica,  feldspar,  or  quartz,  predominates. 

It  is  called  porpJiyritic  granite,  when  the  feldspar  is  in 
large  crystals,  and  appears  over  a  worn  surface  like  thickly 
scattered  white  blotches,  often  rectangular  in  shape. 

Graphic  granite  has  an  appearance  of  small  oriental  cha- 
racters over  the  surface,  owing  to  the  angular  arrangement 
of  the  quartz  in  the  feld- 
spar, or  of  the  feldspar  in 
the  quartz. 

When  the  mica  of  the 
granite   is  wanting,  it  is  *&    \ 
then  a  granular  mixture 
of    feldspar    and    quartz, 
called  granulite  or  lepty- 

"•lie*  Graphic  Granite. 

When  the  feldspar  is  replaced  by  albite,  it  is  called  albite 
granite.  The  albite  is  usually  white,  but  other%vise  resem- 
bles feldspar. 

Granite  is  the  usual  rock  for  veins  of  tin  ore.  It  con- 
tains also  workable  veins  of  pyritous,  vitreous,  and  gray, 
copper  ore,  of  galena  or  lead  ore,  of  zinc  blende,  of  specu- 
lar and  magnetic  iron  ore,  besides  ores  of  antimony,  cobalt, 
nickel,  uranium,  arsenic,  titanium,  bismuth,  tungsten,  and 
silver,  with  rarely  a  trace  of  mercury.  The  rare  cerium  and 
yttria  minerals  are  found  in  granite,  and  mostly  frequently  in 


The  experiments  of  W.  H.  C.  Bartlett,  Lieut.  U.  S.  Engineers,  led 
to  the  following  results. — Amer.  J.  Sci.,  xxii,  136,  1832. 


Granite, 
Marble, 
Sandstone, 
Hammered  copper, 


For  1°F. 
•000004825 
•000005668 
•000009532 
•000009440 


For  180°  F. 
•00086904 
•00102024 
•00171596 
.00169920 


336  ROCKS. 

albitic  granite.  It  also  contains  emerald,  topaz,  corundum, 
zircon,  fluor  spar,  garnet,  tourmaline,  pyroxene,  hornblende, 
epidote,  and  many  other  species. 

Granite  is  one  of  the  most  valuable  materials  for  build- 
ing. The  rock  selected  for  this  purpose,  should  be  fine 
and  even  in  texture,  as  the  coarser  varieties  are  less  dura- 
ble ;  -it  should  especially  be  pure  from  pyrites  or  any  ore  of 
iron,  which  on  exposure  to  the  weather  will  rust  and  destroy, 
as  well  as  deface,  the  stone.  The  only  certain  evidence  of 
durability,  must  be  learned  from  examining  the  rock  in  its  na- 
tive beds  ;  for  some  handsome  granites  which  have  every 
appearance  of  durability,  decompose  rapidly  from  some  cause 
not  fully  understood.  The  more  feldspathic  are  less  en- 
during than  the  quartzose,  and  the  sycnitic  (or  hornblendic) 
variety  more  durable  than  proper  granite  itself.  The  rock, 
after  removal  from  the  quarry,  hardens  somewhat,  and  is  less 
easily  worked  than  when  first  quarried  out. 

Massachusetts  is  properly  the  granite  state  of  the  union. 
New  Hampshire  and  Maine  also  afford  a  good  material. 
The  Quincy  quarries  in  Massachusetts,  south  of  Boston, 
have  for  many  years  been  celebrated.  Besides  this  locality, 
there  are  others  in  the  eastern  part  of  this  state,  between  cape 
Ann  and  Salem,  in  Gloucester,  at  Fall  River,  in  Troy,  in 
Danvers ;  also  south  between  Quincy  and  Rhode  Island,  where 
it  is  wrought  in  many  places,  as  well  as  in  Rhode  Island, 
even  to  Providence.  The  so-called  Chelmsford  granite  comes 
from  Westford  and  Tyngsborough,  beyond  Lowell,  and  an  ex. 
cellent  variety  is  obtained  at  Pelham,  a  short  distance  north 
in  New  Hampshire.  Masses  60  feet  in  length  are  ob- 
tained at  several  of  the  quarries.  They  are  worked  into 
columns  for  buildings,  many  fine  examples  of  which  are 
common  in  Boston,  New  York,  and  other  cities. 

Good  granite  is  also  quarried  in  Waterford,  Greenwich, 
and  elsewhere,  in  Connecticut. 

The  granite  is  detached  in  blocks  by  drilling  a  series  of 
holes,  one  every  few  inches,  to  a  depth  of  three  inches,  and 
then  driving  in  wedges  of  iron  between  steel  cheeks.  In  this 
manner  masses  of  any  size  are  split  out.  There  is  a  choice 
of  direction,  as  the  granite  has  certain  directions  of  easiest 
fracture.  Masses  are  often  got  out  in  long  narrow  strips,  a 
foot  wide,  for  fence  posts.  The  granite  in  a  rough  state 
brings  12  to  15  cents  the  superficial  foot;  ordinary  hewn 
granite  20  to  40  cents  the  foot ;  worked  into  columns  50 
cents  to  1  dollar  the  foot,  according  to  the  size. 


GNEISS MICA    SLATE.  337 

Granite  is  also  used  for  paving,  in  small  rectangular  blocks 
neatly  fitted  together,  as  in  London  and  in  some  parts  of 
New  York  and  other  cities.  The  feldspathic  granite  is  of 
great  value  in  the  manufacture  of  porcelain,  as  remarked 
upon  under  Feldspar. 

Granite  was  much  used  by  the  ancients,  especially  the 
Egyptians,  where  are  obelisks  that  have  stood  the  weather 
for  3000  years. 


GNEISS. 

Gneiss  has  the  same  constitution  as  granite,  but  the  mica 
is  more  in  layers,  and  the  rock  has  therefore  a  stratified  ap- 
pearance. It  generally  breaks  out  in  slabs  a  few  inches  to 
a  foot  thick.  It  is  hence  much  used  both  as  a  building  ma- 
terial and  for  flagging  walks.  The  quarries  in  the  vicinity 
of  Haddam,  Conn.,  on  the  Connecticut  river,  are  very  exten- 
sively opened,  and  a  large  amount  of  stone  is  annually  taken 
out  and  exported  to  the  Atlantic  cities,  even  as  far  as  New 
Orleans.  There  are  also  quarries  at  Lebanon  and  other 
places,  in  Connecticut  ,•  at  Wilbraham,  Millbury,  Monson, 
and  manyot  her  places  in  Massachusetts. 

MICA    SLATE. 

Mica  slate  has  the  constitution  of  gneiss,  but  is  thin  slaty, 
and  breaks  with  a  glistening  or  shining  surface,  owing  to  the 
large  proportion  of  mica,  upon  which  its  foliated  structure 
depends.  Gray  or  silvery  gray  is  a  common  color. 

The  thin  even  slabs  of  the  more  compact  varieties  of  mica 
slate  are  much  used  for  flagging,  and  for  door  and  hearth 
stones  ;  also  for  lining  furnaces.  The  finer  arenaceous  va- 
rieties make  good  scythe  stones. 

It  is  quarried  extensively  of  fine  quality,  in  large  even 

!  slabs,  at  Bolton  in  Connecticut ;  also  in  the  range  passing 

through  Gosheri  and  Chesterfield,  Mass.     It  is  worked  into 

whetstones  in  Enfield,  Norwich,  and  Bellingham,  Mass.,  and 

.  extensively  at  Woonsocket  Hill,  Smithfield,  R.  I.     The  south 

part  of  Chester,  Vt.,  affords  a  slate  like  that  of  Bolton.     Mica 

slate  is  used  at  Salisbury,  Conn.,  for  the  inner  wall  of  the 

'  iron  furnace. 

Hornblende  slate  resembles  mica   slate,  but  has  not  as 
•  glistening  a  luster,  and  seldom  breaks  into  as  thin  slabs.    It 
is  more  tough  than  mica  slate,  and  is  an  excellent  material 
for  flagging. 

29 


338  ROCK.S. 

TALCOSE  SLATE. TALCOSE  ROCK. 

Talcose  slate  resembles  mica  slate,  but  has  a  more  greasy 
feel,  owing  to  its  containing  talc  instead  of  mica.  It  is  usu- 
ally light  gray  or  dark  grayish-brown.  It  breaks  into  thin 
slabs,  but  is  generally  rather  brittle,  yet  it  often  makes  good 
fire-stones. 

A  talcose  slate  in  Stockbridge,  Vt.,  is  worked  for  scythe 
stones  and  hones,  and  is  of  excellent  quality  for  this  purpose. 

Talcose  rock  is  a  kind  of  quartzose  granite,  containing 
more  or  less  talc,  and  often  quite  compact.  It  is  usually  very 
much  intersected  by  veins  of  white  quartz.  Much  of  it 
contains  chlorite  (an  olive-green  mineral)  in  place  of  talc, 
here  and  there  disseminated  :  and  there  is  a  chlorite  slate,  of 
a  dark  green  color,  similar  in  general  characters  to  talcose 
slate.  Talcose  rock  passes  into  a  flinty  quartz  rock. 

The  talcose  rocks  are  to  a  great  extent  the  gold  rocks  of  the 
world,  especially  the  quartzose  veins,  as  mentioned  under 
Gold.  It  contains  the  topaz  of  Brazil,  and  also  euclase,  and 
many  other  minerals. 

STEATITE,    OR    SOAPSTONE. 

Steatite  is  a  soft  stone,  easily  cut  by  the  knife  and  greasy 
in  its  feel.  Its  color  is  usually  grayish-green  ;  but  when 
smoothed  and  varnished  it  becomes  dark  olive -green.  It 
occurs  in  beds,  associated  generally  with  talcose  slate. 

Owing  to  the  facility  with  which  soapstone  is  worked,  and 
its  refractory  nature,  it  is  cut  into  slabs  for  fire  stones  and  other 
purposes,  as  stated  on  page  144.  The  powder  is  employed 
for  diminishing  friction,  and  for  mixing  with  blacklead  in  the 
manufacture  of  crucibles.  It  is  also  used,  as  observed  by 
Dr.  C.  T.  Jackson,  for  the  sizing  rollers  in  cotton  factories, 
one  of  which  is  4£  feet  long  and  5  to  6  inches  in  diameter. 
The  most  valuable  quarries  in  Massachusetts  are  at  Middle, 
field,  Windsor,  Blanford,  Andover,  and  Chester ;  in  Vermont, 
at  Windham  and  Grafton  ;  in  New  Hampshire,  at  Frances- 
town  and  Oxford  ;  in  Orange  county,  North  Carolina.  The 
Francestown  soapstone  sells  at  Boston  at  from  36  to  42  dol- 
lars the  ton,  or  from  3  to  3£  dollars  the  cubic  foot.* 

Steatite  often  contains  disseminated  crystals  of  magnesian 
carbonate  of  lime,  (dolomite,)  and  brown  spar  ;  also  crys- 
tals of  pyrites  and  actinolitc. 

*  Geol.  N.  II.,  by  C.  T.  Jackson,  1844 ;  p.  168. 


SERFEN  TINE. TRAP.  339 

Potstone  is  a  compact  steatite.  Rensselaerite  is  another 
compact  variety,  (page  144,)  found  in  Jefferson  and  St.  Law- 
rence counties,  N.  Y.,  and  used  for  inkstands. 

SERPENTINE. 

This  dark  green  rock  is  ussually  associated  with  talcose 
rocks,  and  often  also  with  granular  limestones.  It  has  been 
described  on  page  145,  where  its  uses  are  alluded  to.  It 
often  contains  disseminated  a  foliated  green  variety  of  horn- 
blende called  diallage.  A  compound  rock  consisting  of  dial- 
lage  and  feldspar,  has  been  called  diallage  rock  or  euphotide. 

TRAP. BASALT. 

Trap  is  a  dark  greenish  or  brownish-black  rock,  heavy 
and  tough.  Specific  gravity  2*8 — 3'2.  It  has  sometimes 
a  granular  crystalline  structure,  and  at  other  times  it  is  very 
compact  without  apparent  grains.  It  is  an  intimate  mixture 
of  feldspar  and  hornblende.  It  is  often  called  greenstone  ; 
and  when  consisting  of  albite  and  hornblende,  it  is  called 
diorite. 

Amygdaloid,  (from  the  Latin  amygdalum,  an  almond,)  is 
a  trap  containing  small  almond-shaped  cavities,  which  are 
filled  with  some  mineral :  usually  a  zeolite,  quartz,  or  chlorite. 

Porphyritic  trap  is  a  trap  containing,  like  porphyritic  gran- 
ite (p.  335,)  disseminated  crystals  of  feldspar. 

Basalt  is  a  rock  resembling  trap,  but  consisting  of  augite 
and  feldspar.  It  varies  in  color  from  grayish  to  black. 
In  the  lighter  colored,  which  are  sometimes  denominated 
graystone,  feldspar  predominates  ;  and  in  the  darker,  iron,  or 
a  ferruginous  augite.  It  often  contains  chrysolite  (or  olivine) 
in  small  grains  of  a  bottle-glass  appearance.  Magnetic  or 
titanic  iron  are  also  frequently  present  in  the  rock.  When 
feldspar  crystals  are  coarsely  disseminated,  it  is  called  'por- 
phyritic basalt;  and  when  containing  minerals  in  small 
nodules,  it  is  amygdaloidal  basalt;  when  consisting  of  labra- 
dorite  and  augite,  it  is  called  dolerite. 

WacJfe  or  toadstone  is  an  earthy  basalt,  or  a  sedimentary 
rock  of  trap  or  basaltic  material. 

Both  trap  and  basalt  occur  in  columnar  forms,  as  at  the 
Giant's  Causeway  and  other  similar  places. 

Trap  and  basalt  are  excellent  materials  for  macadamizing 
roads,  on  account  of  their  toughness.  Trap  is  also  used  for 
buildings.  It  breaks  into  irregular  angular  blocks,  and  is 


340  ROCKS. 

employed  in  this  condition.     For  a  Gothic  building  it  is  well 
fitted,  on  account  of  an  appearance  of  age  which  it  has. 

PORPHYRY. CLINKSTONE. TRACHYTE. 

Porphyry  consists  mainly  of  compact  feldspar,  with  dis- 
seminated crystals  of  feldspar.  Red  or  brownish-red  and 
green,  are  common  colors  ;  but  gray  and  black  are  met  with. 
The  feldspar  crystals  are  from  a  very  small  size  to  half  or 
three  quarters  of  an  inch  in  length,  and  have  a  much  lighter 
shade  of  color  than  the  base,  or  are  quite  white.  It  breaks 
with  a  smooth  surface  and  conchoidal  fracture.  The  specific 
gravity  and  other  characters  of  the  rock  are  the  same  nearly 
as  for  the  mineral  feldspar  ;  the  hardness  is  usually  a  little 
higher  than  in  that  mineral. 

Porphyry  receives  a  fine  polish,  and  has  been  used  for 
columns,  vases,  mortars,  and  other  purposes.  Green  por- 
phyry is  the  oriental  verd  antique  of  the  ancients,  and  was , 
held  in  high  esteem.  The  red  porphyry  of  Egypt  is  also  a 
beautiful  rock.  It  has  a  clear  brownish  red  color,  and  is 
sprinkled  with  small  spots  of  white  feldspar. 

Clinkstone  or  Phonolite  is  a  grayish-blue  rock,  consisting, 
like  porphyry,  mainly  of  feldspar.  It  passes  into  gray  basalt, 
and  is  distinguished  by  its  less  specific  gravity.  It  rings 
like  iron  when  struck  with  a  hammer,  and  hence  its  name. 

Trachyte  is  another  feldspathic  rock,  distinguished  by 
breaking  with  a  rough  surface,  and  showing  less  compact- 
ness than  clinkstone.  It  sometimes  contains  crystals  of 
hornblende,  mica,  or  some  glassy  feldspar  mineral.  It  occurs 
in  volcanic  regions. 

LAVA. OBSIDIAN.— PUMICE. 

The  term  lava  is  applied  to  any  rock  material  which  has 
flowed  in  igneous  fusion  from  a  volcano.  Basalt  is  one  kind 
of  lava  ;  and  when  containg  cellules,  it  is  called  basaltic 
lava.  Trachyte  is  also  a  lava.  There  are  thus  both  feld- 
spathic and  basaltic  lavas.  The  feldspathic  are  light  colored, 
and  of  low  specific  gravity,  (not  exceeding  2'8)  ;  the  basaltic 
vary  from  grayish-blue  to  black,  and  are  above  2'8  in  specific 
gravity.  The  general  term  basaltic  sometimes  includes 
doleritic  lava,  which  is  closely  allied.  Chrysolite  is  often 
present  in  basaltic  lavas ;  and  they  are  not  unfrequently  por- 
phyritic,  or  contain  disseminated  crystals  of  feldspar. 


SHALE  341 

The  light  cellular  ejections  of  a  volcano  are  called  scoria 
or  pumice. 

Pumice  is  feldspathic  in  constitution  ;  it  is  very  porous, 
and  the  fine  pores  lying  in  one  direction  make  the  rock  ap- 
pear to  be  fibrous.  It  is  so  light  as  to  float  on  water.  It  is 
much  used  for  polishing  wood,  ivory,  marble,  metal,  glass, 
etc.,  and  also  parchment  and  skins.  The  principal  localities 
are  the  islands  of  Lipari,  Ponza,  Ischia,  and  Vulcano,  in  the 
Mediterranean  between  Sicily  and  Naples.  Both  scoria 
and  pumice  are  properly  the  scum  of  a  volcano. 

Volcanic  asJies  are  the  light  cinders,  or  minute  particles 
of  rock,  ejected  from  a  volcano  in  the  course  of  an  eruption. 

Obsidian  is  a  volcanic  glass.  It  resembles  ordinary  glass. 
Black  and  smoky  tints  are  the  common  colors.  In  Mexico, 
it  was  formerly  used  both  for  mirrors,  knives  and  razors. 
Pitchstone  is  less  perfectly  glassy  in  its  character,  and  has  a 
pitch-like  luster.  Otherwise  it  resembles  obsidian.  Pearl- 
stone  has  a  grayish  color  and  pearly  luster.  Spherulite  is  a 
kind  of  pearlstone,  occurring  in  small  globules  in  massive 
pearlstone.  Marekanite  is  a  pearl-gray  translucent  obsidian 
from  Marekan  in  Kamschatka. 

ARGILLACEOUS    SHALE,    OR    CLAY    SLATE. ARGILLITE. 

Slate  is  an  argillaceous  rock,  breaking  into  thin  laminae  ; 
shale  a  similar  rock,  with  the  same  structure  usually  less 
perfect  and  often  more  brittle  ;  schist  includes  the  same  va- 
rieties of  rock,  but  is  extended  also  to  those  of  a  much  coarser 
laminated  structure.  The  ordinary  clay  slate  has  the  same 
constitution  as  mica  slate  ;  but  the  material  is  so  fine  that 
the  ingredients  cannot  be  distinguished.  The  two  pass  into 
one  another  insensibly.  The  colors  are  very  various,  and 
always  dull  or  but  slightly  glistening. 

Roofing  slate  is  a  fine  grained  argillaceous  variety,  com- 
monly of  a  dark  dull  blue  or  bluish-black  color,  or  some- 
what purplish.  To  be  a  good  material  for  roofing,  it  should 
split  easily  into  even  slates,  and  admit  of  being  pierced  for 
nails  without  fracturing.  Moreover,  it  should  not  be  ab- 
sorbent of  water,  either  by  the  surface  or  edges,  which  may 
be  tested  by  weighing,  after  immersion  for  a  while  in  water. 
It  should  also  be  pure  from  pyrites  and  every  thing  that  can 
undergo  decomposition  on  exposure. 

Roofing  slates  occur  in  England,  in  Cornwall  and  Devon, 
Cumberland,  Westmoreland. 
29* 


342  ROCKS. 

In  the  United  States,  a  good  material  is  obtained  in  Maine 
at  Barnard,  Piscataquies,  Kennebec,  Bingham  and  elsewhere 
also  in  Massachusetts,  in  Worcester  county,  in  Boylston, 
Lancaster,  Harvard,  Shirley,  and  Peperell ;  in  Vermont,  at 
Guilford,  Brattleborough,  Fairhaven,  and  Dummerston  ;  in 
Hoosic,  New  York  ;  on  Bush  creek  and  near  Unionville, 
Maryland  ;  at  the  Cove  of  Wachitta,  Arkansas.  At  Rutland, 
Vt.,  is  a  manufactory  of  slate  pencils,  from  a  greenish  slate 

These  slate  rocks  are  also  used  for  gravestones  ;  and  we 
cannot  go  through  New  England  cemetries  without  frequent 
regret  that  a  material  which  is  sure  to  fall  to  pieces  in  a  few 
years,  should  have  been  selected  for  such  records. 

Drawing  slate  is  a  finer  and  more  compact  variety,  of 
bluish  and  purplish  shades  of  color.  The  best  slates  come 
from  Spain,  Italy,  and  France.  A  good  quality  is  quarried  in 
Maine  and  Vermont. 

Novaculite,  hone-slate,  or  whet-stone,  is  a  fine  grained  slate, 
containing  considerable  quartz,  though  the  grains  of  this 
mineral  are  not  perceptible.  It  occurs  of  light  and  dark 
shades  of  color,  and  compact  texture.  It  is  found  in  North 
Carolina,  7  miles  west  of  Chapel  Hill,  and  elsewhere ;  in 
Lincoln  and  Oglethorpe  counties,  Georgia ;  on  Bush  creek, 
and  near  Unionville,  Maryland  ;  at  the  Cove  of  Wachitta, 
Arkansas. 

Argillite  is  a  general  term  given  to  argillaceous  or  clay 
slate  rocks.  Many  shales  or  argillites  crumble  easily,  and 
are  unfit  for  any  purpose  in  the  arts,  except  to  furnish  a 
clayey  soil. 

Alum  shale  is  any  slaty  rock  which  contains  decomposing 
pyrites,  and  thus  will  afford  alum  or  sulphate  of  alumina  on 
lixiviation.  (See  under  Alum,  page  128.) 

Bituminous  shale  is  a  dark  colored  slaty  rock  containing 
some  bitumen,  and  giving  ofFa  bituminous  odor. 

Plumbaginous  schist  is  a  clay  slate  containing  plumbago 
or  graphite,  and  leaving  traces  like  black  lead. 

The  Pipestone  of  the  North  American  Indians  was  in  part 
a  red  claystone  or  compacted  clay  from  the  Coteau  de 
Prairies.  It  has  been  named  catlinite.  A  similar  material, 
now  accumulating,  occurs  on  the  north  shore  of  Lake  Supe- 
rior, at  Nepigon  bay.  Another  variety  of  pipestone  is  a  dark 
grayish  compact  argil  lite  ;  it  is  used  by  the  Indians  of  the 
northwest  coast  of  America. 

Agalmatolite  is  a  soft  mineral,  impressible  by  the  nail, 


A~ -••*-. 

iQUARTZ    ROCK.J  343 

and  waxy  in  luster  when  polished,  presenting  grayish  and 
greenish  colors  and  other  shades.  Gr=2*8 — 2'9.  It  has  a 
greasy  feel.  It  consists  of  silica  55*0,  alumina  30*0,  potash 
7'0,  water  3  to  5  per  cent.,  with  a  trace  of  oxyd  of  iron.  It 
is  carved  into  images,  and  is  hence  called  Jigure-stone. 

QUARTZ    ROCK. 

Quartz  rock  is  a  compact  rock  consisting  of  quartz,  and 
often  appearing  granular.  Its  colors  are  light  gray,  reddish 
or  dull  bluish  ;  also  sometimes  brown. 

When  the  granular  quartz  contains  a  little  mica,  it  often 
breaks  in  slabs  like  gneiss  or  mica  slate.  The  itacolumite 
of  Brazil,  with  which  gold  and  topaz  are  associated,  is  a 
micaceous  granular  quartz  rock  of  this  kind. 

Flexible  sandstone  is  an  allied  rock  of  finer  texture.  Gran- 
ular  quartz  graduates  into  the  proper  sandstones,  which  are 
treated  of  for  convenience  on  a  following  page.  The  two 
rocks  are  properly  parts  .of  one  series. 

Granular  quartz  is  one  of  the  most  refractory  of  rocks.  It 
is  consequently  used  extensively  for  hearthstones,  for  the 
lining  of  furnaces,  and  for  lime  kilns.  At  Stafford,  Conn., 
a  loose  grained  micaceous  quartz  rock  is  highly  valued  for 
furnaces  ;  it  sells  at  the  quarry  for  16  dollars  a  ton.* 

Granular  quartz  is  also  used  for  flagging,  and  a  fine 
quarry  is  opened  in  Washington,  near  Pittsfield,  Mass. ;  it 
also  occurs  of  good  quality  at  Tyringham  and  Lee,  Mass. 
In  the  shape  of  cobble  stones,  it  is  a  common  paving  material. 

A  highly  important  use  of  this  rock  is  in  the  manufacture 
of  glass  and  sandpaper,  and  for  sawing  marble.  In  many 
places  it  occurs  crumbled  to  a  fine  sand,  and  is  highly  con- 
venient for  these  purposes.  In  Cheshire,  Berkshire  county, 
Mass.,  and  in  Lanesboro',  Mass.,  it  occurs  of  superior  qual- 
ity, and  in  great  abundance.  It  is  also  in  demand  for  the 
manufacture  of  glass  and  pottery.  In  Unity,  N.  H.,  a  gran- 
ular quartz  is  ground  for  sandpaper  and  for  polishing  powder ; 
the  latter  is  a  good  material  for  many  purposes. 

A  fine  variety  of  granular  quartz  is  a  material  much 
Valued  for  whet-stones. 

BUHRSTONE. 

Buhrstone  is  a  quartz  rock  containing  cellules.  It  is  as 
hard  and  firm  as  quartz  crystal,  and  owes  its  peculiar  value 

*  Rep.  on  Connecticut,  by  C.  U.  Shepard — p.  78. 


344  nocks. 


to  this  quality  and  the  cellules,  which  give  it  a  very  rough 
surface.  In  the  best  stones  for  wheat  or  corn  the  cavities 
about  equal  in  space  the  solid  part.  The  finest  quality 
comes  from  France,  in  the  basin  of  Paris  and  some  adjoin- 
ing districts. 

The  stones  are  cut  into  wedge-shaped  parallelepipeds  called 
panes,  which  are  bound  together  by  iron  hoops  into  large 
millstones.  The  Paris  buhrstone  is  from  the  tertiary  forma- 
tion, and  is  therefore  of  much  more  recent  origin  than  the 
quartz  rock  above  described. 

Buhrstone  of  good  quality  is  abundant  in  Ohio,  and  others 
of  the  western  states.  It  is  associated  there  with  proper 
sandstones,  as  more  particularly  mentioned  on  page  346. 

The  quartz  rock  of  Washington,  near  Pittsfield,  Mass.,  is 
in  some  parts  cellular,  and  makes  good  millstones. 

A  buhrstone  occurs  in  Georgia,  about  40  miles  from  the 
sea,  near  the  Carolina  line  ;  also  in  Arkansas,  near  the 
Cove  of  Wachitta. 

SANDSTONES.  -  GRIT    ROCKS.  -  CONGLOMERATES. 

Sandstones  consist  of  small  grains,  aggregated  into  a  com- 
pact rock.  They  have  a  harsh  feel,  and  every  dull  shade  of 
color  from  white  through  yellow,  red  and  brown  to  black. 
Many  sandstones  are  very  compact  and  hard,  while  others 
break  or  rub  to  pieces  in  the  fingers.  They  usually  consist 
of  siliceous  sand  ;  but  grains  of  feldspar  are  often  present. 
In  many  compact  sandstones  there  is  much  clay,  and  the 
rock  is  then  an  argillaceous  sandstone. 

Sandstones  are  of  all  geological  ages,  from  the  lower  Silu- 
rian to  the  most  recent  period.  The  older  rocks  are  in 
general  the  most  firm  and  compact.  The  "  old  red"  sand- 
stone is  a  sandstone  below  the  coal  in  age  ;  while  the  so 
called  "  new  red"  is  more  recent  than  the  coal.  But  these 
terms  beyond  this  particular  point,  are  of  somewhat  indefi- 
nite application.  The  sandstone  of  the  Connecticut  valley 
is  called  the  new  red  sandstone. 

Grit  rock.  When  the  sandstone  is  very  hard  and  harsh, 
and  contains  occasional  siliceous  pebbles,  it  is  called  a  grit 
rock,  or  millstone  grit. 

Conglomerates.  Conglomerates  consist  mostly  of  pebbles 
compacted  together.  They  are  called  pudding  stone  when 
the  pebbles  are  rounded,  and  breccia  when  they  are  angular. 
They  may  consist  of  pebbles  of  any  kinds,  as  of  granitet 


SANDSTONES.  345 

quartz,  limestone,  etc.,  and  they  are  named  accordinglygrem- 
j/ir,  quartzose,  calcareous,  conglomerates. 

The  use  of  sandstone  as  a  building  material  is  well  known. 
For  this  purpose  it  should  be  free,  like  granite,  from  pyrites 
or  iron  sand,  as  these  rust  and  disfigure  the  structure.  It 
should  be  firm  in  texture,  and  not  liable  to  peel  off  on  ex- 
posure. Some  sandstones,  especially  certain  argillaceous 
varieties,  which  appear  well  in  the  quarry,  when  exposed  for 
a  season  where  they  will  be  left  to  dry,  gradually  fall  tc» 
pieces.  The  same  rock  answers  well  for  structures  beneath 
water,  that  is  worth  nothing  for  buildings.  Other  sandstones 
which  are  so  soft  as  to  be  easily  cut  from  their  bed  without 
blasting,  harden  on  exposure,  (owing  to  the  hardening  of 
silica  in  the  contained  moisture,)  and  are  quite  durable. 
These  are  qualities  which  must  be  tested  before  a  stone 
is  used.  Moreover  it  should  be  considered  that  in  frosty 
climates,  a  weak  absorbent  stone  is  liable  to  be  destroyed  in 
a  comparatively  short  time,  while  in  a  climate  like  that  of 
Peru,  even  sunburnt  bricks  will  last  for  centuries. 

Mr.  Ure  observes,  that  "  such  was  the  care  of  the  ancients 
to  provide  strong  and  durable  materials  for  their  public  edi- 
fices, that  but  for  the  desolating  hands  of  modern  barbarians, 
in  peace  and  in  war,  most  of  the  temples  and  other  public 
monuments  of  Greece  and  Rome  would  have  remained 
perfect  at  the  present  day,  uninjured  by  the  elements  during 
2000  years.  The  contrast  in  this  respect  of  the  works  of 
modern  architects,  especially  in  Great  Britain,  [much  more 
true  of  the  United  States,]  is  very  humiliating  to  those  who 
boast  so  loudly  of  social  advancement ;  for  there  is  scarcely 
a  public  building  of  recent  date  which  will  be  in  existence 
a  thousand  years  hence."  Many  splendid  structures  are 
monuments  (not  endless)  of  folly  in  this  respect.  He  ob- 
serves also  that  the  stone  intended  for  a  durable  edifice  ought 
to  be  tested  as  to  its  durability  by  immersion  in  a  saturated 
solution  of  sulphate  of  soda,  and  exposure  to  the  air  for  some 
days  :  the  crystallization  within  the  stone  will  cause  the  same 
disintegration  that  would  result  in  time  from  frost. 

The  dark  red  sandstone  (freestone)  of  New  Jersey  and 
Connecticut,  when  of  fine  gritty  texture  and  compact,  is  gen- 
erally an  excellent  building  material.  Tiinity  Church  in 
New  York  is  built  of  the  stone  from  Belville,  New  Jersey. 
At  Chatham,  on  the  Connecticut,  is  a  large  quarry,  which 
supplies  great  quantities  of  stone  to  the  cities  of  the  coast ; 


846  ROCKS. 

and  there  are  numerous  others  in  the  Connecticut  valley, 
both  in  Connecticut  and  Massachusetts.  A  variety  in  North 
Haven,  at  the  east  end  of  Mount  Carmcl,  has  been  spoken 
of  as  excellent  for  ornamental  architecture.  That  of  Long- 
meadow  and  Wilbraham,  in  Massachusetts,  is  a  very  fine 
and  beautiful  variety  and  is  much  used.  A  freestone  occurs 
also  at  the  mouth  of  Seneca  creek,  Maryland,  convenient  for 
transportation  by  the  Chesapeake  and  Ohio  canal ;  white 
and  colored  sandstones  occur  also  at  Sugarloaf  mountain, 
Maryland. 

The  sandstone  of  the  Capitol  at  Washington,  is  from  the 
Potomac  ;  it  is  a  poor  material. 

Sandstones  when  splitting  into  thin  layers,  form  excellent 
flagging  stones,  and  are  in  common  use. 

Hard,  gritty  sandstones  and  the  grit  rocks  are  used  for  the 
heartJis  of  furnaces,  on  account  of  their  resistance  to  heat. 
They  are  also  much  used  for  millstones,  and  when  of  firm 
texture,  make  a  good  substitute  for  the  buhrstone. 

The  true  buhrstone  has  been  described  as  a  cellular 
siliceous  rock,  without  an  apparent  granular  texture.  The 
buhrstone  of  Ohio  approaches  this  character ;  it  is  in  part 
a  true  sandstone  containing  fossils  in  some  places,  and  over- 
lying the  coal.  Much  of  it  contains  lime  ;  and  it  is  possible 
that  the  removal  of  the  lime  by  solution,  since  its  deposition, 
may  have  occasioned  its  cellular  character.  It  has  an  open 
cellular  structure  where  quarried  for  millstones.  It  occurs 
in  Ohio,  in  the  county  of  Muskingum,  and  the  counties  south 
and  west  of  south,  on  the  Raccoon  river  and  elsewhere. 
The  manufacture  commenced  in  this  region  in  1807,  and  in 
Richland,  Elk,  and  Clinton,  and  in  Hope  well,  the  manufac- 
ture is  now  carried  on  extensively.  Stones  4  feet  in  diame- 
ter bring  8150.* 

The  "  green  sand"  of  the  cretaceous  formation  contains 
grains  of  silicate  of  iron  and  potash,  to  which  it  owes  its 
greenish  tint.  It  occurs  abundantly  in  New  Jersey  as  a  soft 
rock,  and  is  much  used  for  improving  lands  :  a  value  it  owes 
mostly  to  the  alkali  it  contains. 

Pudding  stones  and  breccias  are  fitted,  in  general,  only  for 
the  coarser  uses  of  stone,  as  for  foundations,  butments  of 
bridges.  Occasionally  when  of  limestone,  they  make  hand- 
some marbles,  as  the  "Potomac  breccia  marble"  on  the 

*  S.  P.  Hildreth,  Geol.  Report,  Ohio. 


LIMESTONES.  347 

Mouocacey,  of  which  the  columns  in  the  Hall  of  Represen- 
tatives at  Washington. 

Porphyry  conglomerates,  basaltic  conglomerates,  pumiceovs 
conglomerates,  consist  respectively  of  pebbles  or  fragments  of 
porphyry,  basalt,  pumice. 

Tufa  is  a  sandrock  consisting  of  volcanic  material,  either 
cinders  or  the  comminuted  lavas.  Pozzuolana  is  a  kind  of 
tufa  found  in  the  vicinity  of  Rome,  Italy.  It  consists  of 
silica  34*5,  alumina  15,  lime  8'8,  magnesia  4*7,  potash  1*4, 
soda  4' 1,  oxyds  of  iron  and  titanium  12,  water  9'2.  Pepe- 
rino  is  a  coarse  sandrock,  made  up  of  volcanic  cinders  or 
fine  fragments  of  scoria,  partially  agglutinated. 

LIMESTONES. 

Limestones  consist  essentially  of  carbonate  of  lime,  and 
belong  to  the  species  calcite,  (p.  1 15,)  or  of  the  carbonates  of 
lime  and  magnesia.  They  are  distinguished  by  being  easily 
scratched  with  a  knife,  and  by  effervescing  with  an  acid. 
They  are  either  compact  or  granular  in  texture  :  the  com- 
pact  break  with  a  smooth  surface,  often  conchoidal ;  the 
granular  have  a  crystalline  granular  surface,  and  the  fine 
varieties  resemble  loaf  sugar. 

Granular  limestone.  The  finest  and  purest  white  crystal- 
line limestones  are  used  for  statuary  and  the  best  carving, 
and  are  called  slaluary  marble.  A  variety  less  fine  in  texture 
is  employed  as  a  building  material.  Its  colors  are  white,  and 
clouded  of  various  shades.  It  often  contains  scales  of  mica 
disseminated,  and  occasionally  other  impurities,  from  which 
the  cloudings  arise. 

The  finest  statuary  marble  comes  from  the  Italian  quarry 
at  Carrara  ;  from  the  Island  of  Paros,  whence  the  name 
Parian  ;  from  Athens,  Greece  ;  from  Ornofrio,  Corsica,  of 
a  quality  equal  to  that  of  Carrara.  The  Medicean  Venus 
and  most  of  the  fine  Grecian  statues  are  made  of  the  Parian 
marble.  These  quarries,  and  also  those  of  the  Islands  of  Scio, 
Samos  and  Lesbos,  afforded  marble  for  the  ancient  temples  of 
Greece  and  Rome.  The  Parthenon  at  Athens  was  con- 
structed of  marble  from  Pentelicus. 

Statuary  marble  has  been  obtained  in  the  United  Sates, 
but  not  of  a  quality  equal  to  the  foreign.  Fine  building 
material  is  abundant  along  the  Western  part  of  Vermont, 
and  south  through  Massachusetts  to  Western  Connecticut 
and  Eastern  New  York.  In  Berkshire  county,  Mass.,  mar- 


348  ROCKS. 

ble  is  quarried  annually  to  the  value  of  $200,000 ;  the  prin* 
cipal  quarries  are  at  Sheffield,  West  Stockbridge,  New 
Ashford,  New  Marlborough,  Great  Barrington,  and  Lanes- 
borough.*  The  columns  of  the  Girard  College  are  from 
Sheffield,  where  blocks  50  feet  long  are  sometimes  blasted 
out;  the  material  of  the  City  Hall,  New  York,  came  from 
West  Stockbridge  ;  that  of  the  Capitol  at  Albany,  from  Lanes- 
boro'.  At  Stoneham  is  a  fine  statuary  marble  ;  but  it.  is  dif- 
ficult to  obtain  large  blocks.  The  variety  from  Great  Bar- 
rington is  a  handsome  clouded  marble.  Some  of  the  West 
Stockbridge  marble  is  flexible  in  thin  pieces  when  first  taken 
out.  There  are  Vermont  localities  at  Dorset,  Rutland, 
Brandon,  and  Pittsford.  In  New  York  extensive  quarries 
are  opened  not  far  from  New  York,  at  Sing  Sing  ;  also  at  Pat- 
terson, Putnam  county  ;  at  Dover  in  Dutchess  county,  N.  Y.  ; 
in  Connecticut  there  are  marble  quarries  at  New  Preston ; 
in  Maine  at  Thomaston  :  in  Rhode  Island  at  Smithfield,  a 
fine  statuary  ;  in  Maryland,  a  few  miles  east  of  Hagerstown  ; 
in  Pennsylvania,  a  fine  clouded  variety,  20  miles  from 
Philadelphia.  A  fine  dun  colored  marble  is  obtained  at  New 
Ashford  and  Sheffield,  Mass.,  and  at  Pittsford,  Vt. 

The  granular  limestone  when  coarse  usually  crumbles 
easily,  and  is  not  a  good  material  for  building.  But  the 
finer  varieties  are  not  exceeded  in  durability  by  any  other 
architectural  rock,  not  even  by  granite.  The  impurities  are 
sometimes  so  abundant  as  to  render  it  useless.  For  statu- 
ary, it  is  essential  that  it  should  be  uniform  in  tint  and  with- 
out seams  or  fissures  ;  the  liability  of  finding  cloudings  within 
the  large  blocks  would  altogether  discourage  their  use  for 
statuary. 

The  common  minerals  in  this  rock  are  tremolite,  asbestus, 
scapolite,  chondrodite,  pyroxene,  apatite,  besides  sphene, 
spinel,  graphite,  idocrase,  mica. 

Verd  antique  marble — verde  antico — is  a  clouded  green 
marble,  consisting  of  a  mixture  of  serpentine  and  limestone, 
as  mentioned  under  Serpentine,  page  147.  It  occurs  at 
Milford,  near  New  Haven,  Connecticut,  of  fine  Quality ;  and 
also  in  Essex  county,  N.  Y.,  at  Moria  and  near  Port  Henry 
on  Lake  Champlain.  A  marble  of  this  kind  occurs  at 
Genoa  and  in  Tuscany,  and  is  much  valued  for  its  beauty 
A  variety  is  called  polzivera  di  Genoa  and  vert  d'Egypte. 


*  Hitchcock's  Geol.  Rep.,  p.  !G2. 


LfMESTOTfES.  349 

The  Cipolin  marbles  of  Italy  are  white,  or  nearly  so,  with 
shad  ings  or  zones  of  green  talc.  The  bardiglio  is  a  gray 
variety  from  Corsica. 

Compact  limestone  usually  breaks  out  easily  into  thick 
plabs,  and  are  a  convenient  and  durable  stone  for  building 
and  all  kinds  of  stone  work.  It  is  not  possessed  of  much 
beauty  in  the  rough  state.  When  polished  it  constitutes  a 
variety  of  marbles  according  to  the  color ;  the  shades  are  very 
numerous,  from  white,  cream  and  yellow  shades,  through 
gray,  dove-colored,  slate  blue  or  brown,  to  black. 

The  Nero-ant ico  marlile  of  the  Italians  is  an  ancient  deep 
black  marble  ;  the  paragone  is  a  modern  one,  of  a  fine  black 
color,  from  Bergamo  ;  and  panno  di  morte  is  another  black 
marble  with  a  few  white  fossil  shells. 

The  rosso-anlico  is  deop  blood-red,  sprinkled  with  minute 
while  dots.  The  giallo  anlico,  or  yellow  antique  marble,  is 
drep  yellow  with  black  or  yellow  rings.  A  beautiful  mar- 
ble from  Sienna,  brocalello  di  Siena,  has  a  yellow  color,  with 
huge  irregular  spots  and  veins  of  bluish-red  or  purplish. 
The  mandclato  of  the  Italians  is  a  light  red  marble,  with 
yellowish-white  spots  ;  it  is  found  at  Luggezzana.  At 
VITOIKI,  there  is  ;i  red  marble,  inclining  to  yellow,  and  ano- 
ther with  large  white  spots  in  a  reddish  and  greenish  paste. 

The  black  marble  used  in  the  United  States  comes  mostly 
from  Shoivham,  Vt.,  and  other  places  in  that  state  near  Lake 
Chumplain.  '\\vBristol  marble  of  England  is  a  black  mar- 
hie  containing  a  few  white  shells,  and  the  Kilkenny  is  another 
similar.  There  are  several  quarries  at  Isle  La  Motte.  It 
is  quarried  also  near  Pittsburgh  and  Glenn's  Falls,  N.  Y. 

The  parlor  is  a  Genoese  marble  very  highly  esteemed.  It 
is  deep  black,  with  elegant  veinings  of  yellow.  The  most 
beautiful  comes  from  Porto-Venese,  and  under  Louis  XIV  a 
great  deal  of  it  was  worked  up  for  the  decoration  of  Versailles. 

Gray  and  dove-colored  compact  marbles  are  common 
through  New  York  and  the  states  West. 

The  bird's-eye  marble  of  Western  New  York  is  a  compact 
limestone,  with  crystalline  points  scattered  through  it. 

Ruin  marble  is  a  yellowish  marble,  with  brownish  sha- 
dings  or  lines  arranged  so  as  to  represent  castles,  towers  or 
cities  in  ruins.  These  markings  proceed  from  infiltrated 
iron.  It  is  an  indurated  calcareous  marl. 

Oolilic  marble  has  usually  a  grayish  tint,  and  is  speckled 
with  rounded  dots,  looking  much  like  the  roe  of  a  fish. 

30 


350  4  ROCKS. 

Shell  marble  contains  scattered  fossils,  and  may  be  of  dif- 
ferent colors.  It  is  abundant  through  the  United  States. 
Crinoidal  or  encritiital  marble  differs  only  in  the  fossils  being 
mostly  remains  of  encrinites,  resembling  thin  disks.  Large 
quarries  are  opened  in  Onondaga  and  Madison  counties,  N. 
Y.,  and  the  polished  slabs  are  much  used.  Madreporit 
marble  consists  largely  of  corals,  and  the  surface  consists  of 
delicate  stars  :  it  is  the  pietra  stellaria  of  the  Italians.  It  is 
common  in  some  of  the  states  on  the  Ohio.  Fire  marble,  or 
lumachelle,  is  a  dark  brown  shell  marble,  having  brilliant 
fire  or  chatoyant  refections  from  within. 

Breccia  marbles  and  pudding  stone  marbles  are  the  pol- 
ished calcareous  breccia  or  pudding  stone,  alluded  to  on 
page  346. 

Stalagmites  and  stalactites  (page  116)  are  frequently  pol- 
ished, and  the  variety  of  banded  shades  is  often  highly  beautiful. 
The  Gibraltar  stone,  so  well  known,  is  of  this  kind.  It  comes 
from  a  cavern  in  the  Gibraltar  rock,  where  it  was  deposited 
from  dripping  water.  It  is  made  into  inkstands,  letter-holders, 
and  various  small  articles. 

Wood  is  often  petrified  by  carbonate  of  lime,  and  occasion- 
ally whole  trunks  are  changed  to  stone.  The  specimens 
show  well  the  grain  of  the  wood,  and  some  are  quite  hand- 
some when  polished. 

Marble  is  sawn  by  means  of  a  thin  iron  plate  and  sand, 
either  by  hand  or  machinery.  In  polishing,  the  slabs  are 
first  worn  down  by  the  sharpest  sand,  either  by  rubbing  two 
slabs  together  or  by  means  of  a  plate  of  iron.  Finer  sand  is 
afterwards  used,  and  then  a  still  finer.  Next  emery  is  ap- 
plied of  increasing  fineness  by  means  of  a  plate  of  lead  ;  and 
finally  the  last  polish  is  given  with  tin-putty,  rubbed  on  with 
coarse  linen  cloths  or  baggings,  wedged  tight  into  an  iron 
planing  tool.  More  or  less  water  is  used  throughout  the 
process. 

Quicklime.  Limestone  when  burnt  produces  quicklime, 
owing  to  the  expulsion  of  the  carbonic  acid  by  the  heat. 
The  purest  limestone  affords  the  purest  lime,  (what  is  called 
fat  lime.)  But  some  impurities  are  no  detriment  to  it 
for  making  mortar,  unless  they  are  in  excess.  Hydraulic 
lime,  which  is  so  called  because  it  will  set  under  water,  is 
made  from  limestone  containing  some  clay,  silica,  and  often 
magnesia.  The  French  varieties  contain  2  or  3  per  cent, 
of  magnesia,  and  10  to  20  of  silica  and  alumina  or  clay.  The 


LIMESTONES.  351 

varieties  in  the  United  States  contain  20  to  40  per  cent,  of 
magnesia,  and  12  to  30  per  cent,  of  silica  and  alumina.  A 
variety  worked  extensively  at  Rondout,  N.  Y.,  afforded  Prof. 
Beck,  carbonic  acid  34*20,  lime  25*50,  magnesia  12*35,  silica 
15*37,  alumina  9*13,  peroxyd  of  iron  2*25.*  Oxyd  of  iron 
is  rather  prejudicial  than  otherwise. 

In  making  mortar,  the  lime  is  mixed  with  water  and 
siliceous  sand.  The  final  strength  of  the  mortar  depends 
principally  on  the  formation  of  a  compound  between  water, 
the  silica  (or  sand)  and  the  lime  ;  of  course  therefore  the 
finer  the  sand,  the  more  thorough  the  combination.  In 
hydraulic  lime,  there  is  silica  and  alumina  present  in  a  thor- 
oughly disseminated  and  finely  divided  state,  which  is  favor- 
able for  the  combination  alluded  to ;  and  to  this  fact  appears 
to  be  mainly  owing  its  hydraulic  character.  Much  less  sand 
is  added  in  making  mortar  from  this  lime  than  from  that  of 
ordinary  limestone. 

Pozzuclana  (page  347)  forms  a  hydraulic  cement  when 
mixed  with  a  little  lime  and  water.  Similar  cements  may  be 
made  with  tufa,  pumice  stone,  and  slate  clay,  by  varying  the 
proportions  of  lime  ;  these  materials  consist  essentially  of 
silica  and  alumina  or  magnesia  with  alkalies,  and  often  some 
lime,  and  therefore  produce  the  same  result  as  with  hydrau- 
lic li me  stone. 

In  the  burning  of  lime,  the  most  common  mode  is  to  erect 
a  square  or  circular  furnace  of  stone,  with  a  door  for  manag- 
ing the  fire  below.  An  arched  cavity  for  the  fire  is  first 
made  of  large  pieces  of  limestone,  and  then  the  furnace 
is  filled  with  the  stone  placed  loosely  so  as  to  admit  of  the 
passage  of  the  flame  throughout :  the  carbonic  acid  is  ex- 
pelled  by  the  heat,  and  when  the  fires  are  out,  the  lime  now 
in  the  state  of  quicklime,  or  in  other  words,  pure  lime,  is 
taken  out.  Great  economy  of  fuel  is  secured  by  means  of 
what  is  called  a  perpetual  kiln.  The  cavity  within  is  best 
made  nearly  of  the  shape  of  an  egg  with  the  narrow  end 
uppermost.  The  inner  walls  are  of  quartz  rock,  mica  slate, 
or  some  refractory  stone  or  fire  brick,  and  between  the  inner 
and  outer  there  is  a  layer  of  cinders  or  ashes,  as  in  the  iron 
furnace,  page  233.  Below  are  three  or  more  openings  for 
furnaces  which  lead  into  the  main  cavity,  a  few  feet  from  the 
bottom ;  and  alternate  with  these  are  other  openings  at  a 

*  Mineralogy  of  New  York,  page  78. 


352  ROCKS, 

lower  level  for  withdrawing  the  lime.  The  lime  is  taken 
out  below  and  the  stone  thrown  in  above,  and  this  may  be 
kept  up  without  intermission  as  long  as  the  kiln  lasts.  Be- 
neath the  furnaces  there  are  also  ash  pits.  Such  a  kiln  is 
most  convenient  for  being  filled  and  emptied  when  situated 
on  a  side  hill. 

The  localities  of  limestone  in  the  United  States  are  too 
common  to  need  enumeration.  Hydraulic  limestone  is  also 
abundant. 

Quicklime  is  much  used  for  improving  lands ;  also  for 
clarifying  the  juice  of  the  sugar  cane  and  beet  root ;  for  puri- 
fying coal  gas  ;  for  clearing  hides  of  their  hair  in  tanneries, 
and  for  various  other  purposes. 

SAND. CLAY. 

The  loose  or  soft  material  of  the  surface  of  the  earth  con- 
sists of  sand,  clay,  gravel  or  stones,  and  what  we  call  in  general 
terms,  "soil  or  earth.  These  materials  are  either  in  layers 
or  irregular  beds.  Most  clay  beds,  and  many  of  gravel, 
when  cut  through  vertically,  show  indications  of  horizontal 
layers,  a  result  of  deposition,  or  distribution*  by  water. 

In  geological  language,  these  stratified  deposits  are  often 
classed  with  rocks,  as  they  graduate  into  true  rocks,  and  dif- 
fer only  in  the  amount  of  cementing  material. 

The  ordinary  constituents  of  earth  are  quartz,  feldspar  or 
clay,  oxyd  of  iron  and  lime  ;  but  these  vary  with  the  source 
from  whence  they  are  derived  When  the  rock  that  has 
afforded  the  soil  is  granite,  mica  slate,  or  the  allied  rocks, 
mica  is  usually  present,  as  well  as  feldspar  and  quartz  ;  so 
a  quartzose  rock  will  furnish  siliceous  gravel ;  a  magnesian, 
will  give  magnesia  to  the  soil ;  calcareous,  lime  ;  trap,  the 
ingredients  of  decomposed  feldspar  or  hornblende.  The 
material  will  be  coarse  or  gravelly,  or  fine  earthy,  according 
to  the  nature  of  the  rock,  or  the  condition  under  which  it  is 
worn  down,  or  its  subsequent  distribution  by  flowing  waters. 
Besides  the  prominent  constituents  mentioned,  there  are 
small  proportions  of  phosphates,  nitrates,  chlorids,  etc.,  toge- 
ther with  the  results  of  vegetable  decomposition  ;  and  these 
comparatively  rare  ingredients  are  of  great  importance  to 
growing  vegetation.  The  pebbles  of  a  soil  are  commonly 
siliceous,  as  this  kind  resists  wear  most  effectually. 

Sand  is  usually  pulverized  quartz,  often  with  some  feldspar. 
Clay  is  a  plastic  earth,  consisting  mainly  of  alumina  on# 


SAND.  353 

third  part,  and  silica  (quartz)  two  thirds.  It  owes  its  plas- 
ticity to  the  alumina,  and  ceases  to  be  called  clay  when  the 
proportion  of  silica  is  too  great  for  plasticity.  It  is  afforded 
by  the  decomposition  of  feldspar  and  all  argillaceous  rocks. 
Oxyd  of  iron,  carbonate  of  lime,  and  magnesia  are  often 
present  in  clays. 

Sand  for  glass  manufacture  should  be  pure  silica,  free 
from  a  taint  of  iron.  This  purity  is  apparent  in  the  clear- 
ness of  the  grains,  under  a  lens,  or  their  white  color.  The 
sand  of  Cheshire  and  Lanesboro',  in  Massachusetts,  is  a 
beautiful  material. 

In  the  manufacture  of  gluss,  the  object  is  to  form  a  trans- 
parent fusible  compound,  and  not  an  opaque  infusible  one  as 
in  pottery.  This  result  is  secured  by  heating  together  to 
fusion,  silica  (quartz  sand  or  flint  powder)  and  the  alkali  pot- 
ash or  soda.  The  ingredients  combine  and  produce  a  sili- 
cate of  potash  or  soda — in  other  words,  glass. 

Besides  these  ingredients,  lime  or  oxyd  of  lead  are  added 
for  glass  of  different  kinds.  A  small  proportion  of  lime  in- 
creases the  density,  hardness,  and  luster  of  glass,  producing 
a  specific  gravity  between  2*5  and  2' 6  ;  while  with  lead  a 
still  denser  material  is  formed — called  crystal  or  Jlint  glass — 
whose  specific  gravity  is  from  3  to  3'6. 

From  7  to  20  parts  of  lime  are  added  for  100  of  silica,  and 
25  to  50  of  calcined  sulphate  or  carbonate  of  soda;  common 
salt  (chlorid  of  sodium)  may  also  be  employed.  A  good 
colorless  glass  has  been  found  by  analysis  to  consist  of  silica 
76*0,  potash  13'6,  and  lime  10*4  parts,  in  a  hundred.  For 
coarse  bottle-glass,  wood-ashes  and  coarse  sea-weed  soda, 
called  kelp,  or  else  pearlashes,  are  used  along  with  siliceous 
sand  and  broken  glass.  For  a  hard  glass,  the  proportion  of 
alkali  is  small. 

The  best  English  crystal  glass  analyzed  by  Berthier,  af- 
forded 59  parts  of  silica,  9  of  potash,  28  of  oxyd  of  lead,  and 
1  '4  of  oxyd  of  manganese.  Crown  glass  contains,  in  general, 
less  alkali  than  crystal  glass,  and  is  superior  in  hardness. 
The  alkali,  moreover,  in  England,  is  soda  instead  of  potash. 
Plate  glass  also  contains  soda,  and  this  soda  (the  carbonate) 
is  prepared  with  great  care.  The  proportions  are  7  parts  of 
sand,  1  of  quicklime,  2£  of  dry  carbonate  of  soda,  besides 
cullet  or  broken  plate. 

The  materials  are  first  well  pounded  and  sifted,  and  mixed 
into  a  fine  paste  ;  they  are  then  heated  together  in  pots  made 
30* 


354  nocKS. 

of  a  pure  refractory  clay,  until  fusion  has  taken  place  and  the 
material  has  settled.  The  glass  is  afterwards  worked  by 
blowing,  or  moulded,  into  the  various  forms  it  has  in  market ; 
and  it  is  finally  annealed — or  in  other  words,  is  very  slowly 
cooled— to  render  it  tough.  A  little  oxyd  of  manganese  is 
usually  employed  to  correct  the  green  color  which  glass  is 
apt  to  derive  from  any  oxyd  of  iron  present.  But  if  the  man- 
ganese is  in  excess,  it  gives  a  violet  tinge  to  it. 

The  following  chemical  distribution  of  glasses  has  been 
proposed : 

Soluble  glass.  A  simple  silicate  of  potash  or  soda,  or  of 
both  of  these  alkalies. 

Bohemian  or  crown  glass.     Silicate  of  potash  and  lime. 

Common  window  and  mirror  glass.  Silicate  of  soda  and 
lime ;  sometimes  also  of  potash. 

Bottle  glass.     Silicate  of  soda,  lime,  alumina,  and  iron. 

Ordinary  crystal  glass.     Silicate  of  potash  and  lead. 

Flint  glass.  Silicate  of  potash  and  lead  ;  more  lead  than 
in  the  preceding. 

Strass.     Silicate  of  potash  and  lead — still  more  lead. 

Enamel.  Silicate  and  stannate,  or  antimonate  of  potash 
or  soda  and  lead. 

Glass  was  manufactured  by  the  Phoenicians,  and  the  later 
Egyptians.  According  to  Pliny  and  Strabo,  the  glass  works 
of  Sidon  and  Alexandria  were  famous  in  their  times,  and 
produced  beautiful  articles.  The  Romans  employed  glass 
to  some  extent  in  their  windows,  and  remains  of  this  glass 
are  found  in  Herculaneum.  Window  glass  manufacture  was 
first  commenced  in  England  in  1557. 

Sand  for  casting  is  a  fine  siliceous  sand,  containing  a  little 
clay  to  make  it  adhere  somewhat  and  retain  the  forms  into 
which  it  may  be  moulded.  It  must  be  quite  free  from  lime. 

Tripoli  is  a  fine  grained  earthy  deposit,  having  a  dry, 
harsh  feel  and  a  white  or  grayish  color.  It  contains  90  per 
cent,  of  silica,  mostly  derived  from  the  casts  of  animalcules. 
It  is  valuable  as  a  polishing  material. 

Marl.  Marl  is  a  clay  containing  carbonate  of  lime.  The 
material  is  valuable  as  manure.  The  term  is  also  improper- 
ly applied  to  any  clayey  earth  used  in  fertilizing  land.  The 
green  sand  in  New  Jersey  is  sometimes  called  marl. 

Fuller's  earth  is  a  white,  grayish,  or  greenish-white  earth, 
having  a  soapy  feel,  which  was  formerly  used  for  removing 
oil  or  grease  from  woolen  cloth.  It  falls  to  pieces  in  water, 


35* 

and  forms  a  paste  which  is  not  plastic.  A  variety  consists 
of  silica  44'0,  alumina  23*1,  lime  4*1,  magnesia  2*0,  pro- 
toxyd  of  iron  2-0.  Gr=2'45. 

Lithomarge  is  a  compact  clay  of  a  fine  smooth  texture, 
and  very  sectile.  Its  colors  are  white,  grayish,  bluish- white, 
reddish- white,  or  ocher-yellow,  with  a  shining  streak.  Gr= 
2*4 — 2-5.  The  tuesite  of  Thomson,  a  white  lithomarge  from 
the  banks  of  the  Tweed,  is  said  to  make  good  slate  pencils, 

Clay  for  bricks  is  the  most  ordinary  kind  ;  it  should  have 
slight  plasticity  when  moistened,  and  a  fine  even  character 
without  pebbles.  It  ordinarily  contains  some  hydrated  oxyd 
of  iron,  which  when  heated  turns  red  by  the  escape  of  the 
water  in  its  composition,  which  reduces  it  to  the  red  oxyd  of 
iron,  and  gives  the  usual  red  color  to  the  brick.  It  also  fre- 
quently contains  lime ;  but  much  lime  is  injurious,  as  it 
renders  the  brick  fusible.  A  clay  is  extensively  employed 
at  Milwaukie,  in  Michigan,  which  contains  no  iron,  and 
produces  a  very  handsome  cream-colored  brick.  About 
9,000,000  of  this  kind  of  brick  were  made  at  that  place  in 
1847. 

In  making  bricks,  the  clay  is  first  well  worked  by  the  tread* 
ing  of  cattle  or  by  machinery  :  after  this,  it  is  moulded  in 
moulds  of  the  requisite  size,  (9|  inches,  by  4|  and  2$,)  and 
then  taken  out  and  laid  on  the  ground.  A  good  workman 
will  make  by  hand  5000  in  a  day,  and  the  best  10,000. 
After  drying  till  stiff  enough  to  bear  handling,  the  bricks  are 
trimmed  off  with  a  knife  when  requiring  it,  and  piled  up  in 
long  walls  for  farther  drying.  They  are  then  made  into  a 
kiln  by  piling  them  in  an  open  manner,  (so  that  the  flame 
and  heated  draft  may  have  passage  among  them,)  and  leav- 
ing places  beneath  for  the  fires.  The  heat  is  continued  48 
hours  or  more. 

The  best  brick  are  pressed  in  moulds.  They  have  a 
smooth,  hard  surface.  Near  Baltimore,  Md.j^bricks  are  thus 
made  by  a  machine,  worked  by  a  single  horse,  which  will 
mould  30,000  bricks  in  12  hours  ;  the  bricks  are  dry  enough 
when  first  taken  from  the  mould  for  immediate  burning. 

Burnt  bricks  were  not  used  in  England  before  the  elev- 
enth century,  when  they  were  employed  in  the  construction 
ef  the  abbey  of  St.  Albans.  But  they  date  historically  as 
far  back  as  the  city  of  Babylon.  Unburnt  bricks  have  also 
been  used  in  all  ages.  Those  of  Egyptian  and  Babylonish 
times  were  made  of  worked  clay  mixed  with  chopped  straw, 


SAND CLAY. 

to  prevent  it  from  falling  to  pieces*  The-  adobies  of  Perm, 
are  large  sun-baked  bricks  or  blocks  of  clay ;  and  in  that 
dry  climate  they  are  very  durable. 

Clay  for  Fire-bricks  should  contain  no  lime,  magnesia,, 
or  iron,  as  its  value  depends  on  its  being  very  refractory. 
There  is  a  large  manufactory  in  the  United  States,  at  Balti- 
more, from  the  tertiary  clays  of  eastern  Maryland*  In  Eng- 
land a  slate  clay  from  the  coal  series  is  employed. 

Potter's  clay  andpipe  <  lay  are  pure  plastic  clays,  free  from 
iron,  and  consequently  burning  white.  The  clay  of  Mil- 
waukie,  from  which  the  cream-colored  bricks  are  mader 
is  much  used  also  for  pottery. 

In  the  manufacture  of  coarse  pottery,  the  clay  is  worked 
with  water  and  tempered  ;  and  then  the  required  form  of  a 
pot  or  pan  is  given  on  a  wheel.  The  ware  is  dried  under 
cover  for  a  while,  and  nest  receives  the  glaze  in  a  cream- 
like  state.  The  glaze  for  the  most  common  ware  consists 
of  very  finely  pulverized  galena,  mixed  with  clay  and  water. 
The  waro  after  drying  again  is  next  placed  in  the  kiln, 
which  is  very  gradually  heated ;  the  heat  causes  the  baking 
of  the  clay,  and  drives  off  .the  sulphur  of  the  galena,  thus 
producing  an  oxyd  of  lead,  which  forms  a  kind  of  glass  (or 
glaze,)  with  the  alumina.  For  a  better  stone  ware,  common 
salt  is  used,  and  it  is  put  on  after  the  baking  has  begun. 

For  the  finer  earthenware,  a  mixture  of  red  and  white 
lead,  feldspar,  silica  and  flint-glass,  is  used  for  a  glaze,  the 
proportions  differing  according  to  the  ware.  The  clay  for 
this  ware  is  mixed  with  flint  powder  (ground  flints  or  sand,) 
to  render  it  less  liable  to  contract  or  break,  and  it  is  worked 
with  great  care,  and  through  various  processes  to  prepare  it 
for  moulding.  The  ware  is  usually  baked  to  a  biscuit,  be- 
fore the  glazing  is  put  on,  as  in  the  manufacture  of  porcelain. 

Kaolin  or  porcelain  clay,  is  derived  from  the  decomposi- 
tion of  feldspar,  as  stated  on  page  117.  The  foreign  kaolin 
occurs  in  Saxony ;  in  France  at  St.  Yrieux-la-Perche,  near 
Limoges  ;  in  Cornwall,  England  ;  also  in  China  and  Japan. 
The  kaolin  used  at  the  Philadelphia  porcelain  works  comes 
mostly  from  the  neighborhood  of  Wilmington,  Delaware. 

The  name  kaolin  is  a  corruption  of  the  Chinese  Kau- 
ling,  meaning  high-ridge,  the  name  of  a  hill  near  Jauchau 
Fu,  where  this  material  is  obtained. 

In  the  manufacture  of  porcelain,  the  kaolin,  and  also  the 
other  ingredients,  are  first  ground  up  separately  to  an  im- 


«A^D CLAY. 


357 


palpable  powder.  The  kaolin  is  mixed  with  a  certain  pro- 
portion #f  feldspar,  iilnt  and  lirae.  The  whole  are  worked 
up  together  in  water,  by  mallets  and  spades,  and  well  knead- 
ed by  the  hands  and  sometimes  the  feet  of  the  workmen. 
The  plastic  material  is  then  laid  aside  m  masses  of  the  size  of 
a  reaii's  feexd,  and  kept  damp  till  required ;  ihe  dough,  as  it  is 
called,  is  now  ready  for  the  potter's  lathe,  (or  other  means,) 
by  which  it  is  moulded  into  the  varioas  forms  of  china  ware. 
After  moulding,  they  are  slowly  arid  thoroughly  dried,  and 
them  taken  to  the  lain,  for  a  preliminary  baking.  They  come 
out  in  the  state  of  bisc&it,  and  are  ready  for  painting  and 
glazing.  The  colors  are  metallic  oxyds,  which  are  put  OH 
either  from  a  wet  copper-plate  impression  on  bibulous  paper, 
or  by  meaes  of  a  brush.  The  former  is  used  for  flat  sur- 
faces ;  the  paper  is  rubbed  on  carefully  to  transfer  the  im- 
pression to  the  porcelain,  and  is  then  wet  and  washed  off. 
It  is  tfeen  carefully  heated  to  evaporate  any  oil  or  grease  era- 
ployed  in  the  printing.  The  glaze  is  made  of  a  quartzose 
ieldspar;  it  is  ground  to  a  very  fine  powder  and  worked  into 
a  paste  with  water,  and  a  little  vinegar-  The  articles  are 
dipped  for  an  Instant  into  this  milky  fluid,  and  as  they  absorb 
the  water  they  come  oat  with  a  delicate  layer  of  feldspar  in 
a  dry  state.  They  atre  touched  with  a  brush  wherever  not 
well  corered.  They  are  then  ready  to  be  finally  baked  in 
the  kiln,  for  which  purpose  each  vessel  is  placed  in  a  sepa- 
rate baked  clay  ease  or  receptacle,  called  a  sagger.  In  this 
process  the  material  undergoes  a  softening,  amounting  al- 
most to  a  partial  fusion,  and  thus  receives  Uae  translucency 
which  distinguishes  porcelain  from  earthen  or  stone  ware. 

The  blue  color  of  common  china  is  produced  by  means 
of  oxyd  of  cobalt ;  carmine,  purple  and  violet,  by  means  of 
chlorid  of  gold ;  red  of  all  shades  by  oxyd  of  iron  ;  yellow 
fcy  oxyd  of  lead,  or  white  oxyd  of  antimony  and  sand ;  green 
by  oxyd  of  copper  or  carbonate  of  lead  ;  brown  by  oxyd  of 
iron,  manganese,  or  copper.  A  steel  luster  is  produced  from 
chlorid  of  platinum. 

The  best  Sevres  ware  is  made  from  63  to  70  parts  of 
kaolin,  22  to  15  of  feldspar,  nearly  10  of  flint,  and  5  or  6  of 
chalk.  In  China  the  kaolin  is  mixed  with  a  quartzose  feld- 
spar rock,  consisting  mainly  of  quartz,  called  peh-tun-tsz. 

Soapsforue  is  sometimes  used  in  this  manufacture  ;  and  as 
it  substitutes  magnesia  for  a  part  of  the  potash*  it  makes  a 
harder  ware  ^  but  it  is  also  more  brittle- 


Z58  LOCALITIES    &F   MINERALS. 


CATALOGUE  OF  AMERICAN  LOCALITIES  OF 
MINERALS. 

The  following  catalogue  may  aid  the  mmeralogical  tourist 
in  selecting  his  routes  and  arranging  the  plan  of  a  journey. 
Only  important  localities,  affording  cabinet  specimens,  are  in 
general  included.  The  names  of  those  minerals  which  are 
obtained  in  good  specimens  at  the  several  localities,  are  dis- 
tinguished by  italics.  When  the  specimens  are  remarkably 
good1,  an  exclamation  mark  (!)  has  been  added,  or  two  of 
these  marks  (!!)  when  the  specimens  are  c^uke  unique. 

MAINE. 

Mt.  Abraham. — AndSalusite,  staurotid'e. 

Albany. — Beryl !  green  and  black  tourmalines,  fddspar,  ross  (fwirt «. 

Albion. — Iron  pyrites. 

Aroostook. — Red  hematite. 

Bingham. — Massive  pyrites,  galena,  blende,  andalusite. 

Blue  Hrh"  Bay. — Arsenical  iron,  molybdenite!  galena,  apatite*!  fluoy 
spar!  black  tourmaline,  (Long  Cove,),  biack  oxyd  of  manganese,  (Os~ 
good's  farm,)  red  manganese,  bog  manganese,  wolfram. 

Bowdoinham. — Beryl,  molybdenite. 

Brunswick^-Gree/i  mica,  garnet !  black  tourmaline  !  molybdenite-. 

Buckfield. — Garnet,  (estates  of  Waterman  and  Low,)  iron  ore. 

Camdage  farm. — (Near  the  tide  mills,)  molybdenite,  wolfram. 

Camden. — Made. 

Garmel,  (Penobscot  county.) — Ch:ay  antinwny^ 

Corinna. — Iron  pyrites,  arsenical  pyrites 

Deer  Me. — Serpentine,  vetd  antique,  asbestus,  diailage. 

Dexter. — Galena,  pyrites,  blende,  copper  pyrites,,  green  tale. 

Dixfield. — Native  copperas,  graphite. 

Farmington. — (Norton's  ledge ^.  pyrites,  graphite,  bog  ore-. 

Georgetown. — (Parker's  island,)  beryl !  bla«k  tourmaline. 

Greenwood. — Graphite, black  manganese. 

Hart  well . — Staurotide . 

Lenox. — Galena,  pyromorphite. 

Lewiston. — Garnet. 

Litchfield. — flaityne,  neyheline,  zircon. 

Lubec  lead  mines. — Galena,  copper  pyrites,  llgnde-,  pyr0mer]jfeite,a* 
•re  of  bismuth. 

Newfield,  (Bond^s  mt.) — Mispickel,  olive  phosphate  of  iron  in  botry,- 
eidal  masses. 

Paris. — Green.'  rod.'.'  biack^and  blue  tourmaline  !  inUa  !  lepidolite! 
feldspar,  allnte,  quartz  crystals!  rost  quartz,. blende: 

Parsonsfield. — Idocrase  .'  yellow  garnet,  pargasitet  adularia,  scapo* 
lite,  galena,  blende,  copper  pyrites. 

Perry. — Prehnite  and  calc  t-par,  (above  Loring's  cove,)  quartz  crystal, 
calc  spar,  aaaLcuae,  apoplwllite^agtkte,  (Gin  cove.); 


LOCALITIES    OF    MINERALS,  359 

Peru. — Crystallized  pyrites. 

Phipsburg. —  Yellow  garnet-!  manganesian garnet,  idecrase,  parga- 
vite,  axinitt,  laumonite-!  chabazile,  an  ore  of  cerium, 

Poland. — Idocrase. 

Raymond. — Magnetic  iron,  scapolite,  pyroxene,  lepidolite,tremolittet 
,  hornblende. 

Rumford. — Yellow  g<trnet,  idacrase,  pyroxene,  apatite,  scapolite, 
graphite, 

Searsmont, — Andalusitc. 

Streaked  mountain. — Beryl '.  black  tourmaline,  mica,  garnet. 

Thomaston. — Calc  spar,  tremolite,  hornblende,  sphene>  arsenical  iroH, 
(Owl's  head,)  black  manganese,  (Dodge's  mountain.) 

Warren. — Galena,  blende. 

Waterville. — Crystallized  pyrites. 

Windham,  (near  the  bridge.)- — Stauretide!  spodumene,  garnet. 

Woodstock,  (New  Brunswick.) — Graphite,  specular  iron, 

NEW  HAMPSHIRE. 

Acworth, — Beryl!  mica .'/  tourmaline,  feldspar,  albitc,  rise  quartz, 
i  solumbite ! 

Alstead,— Mtcall  albite,  black  tourmaline. 

Aniherst. — Idocrase  !  yellow  garnet,  pargaske,  calc  spar, 

Bartlett. — Magnetic  iron,  sf  scalar  iron, brown  iron  ore  in  large  veins 
near  Jackson  (on  "  Bald  face  mountain") — quartz  crystals,  smoky 
{\iartz. 

Bath. — Galena. 

Bellows  Falls. — Kyanite,  wavellite,  near  Saxton's  river. 

Benton. — Quartz  crystals, 

Canaan. — Gold  in  pyrites. 

Charlestown. — Staurotide  made  i  andalusite-macle,  bog  iron  ore, 

Cornish. — Gray  antimony,  antimonial  argentiferous  gray  copper,  rtt- 
tile  in  quartz  !! 

Eaton,  (3  m.  S.  of.) — Galena,  blende!  copper  pyrites,  limonite,  (six 
mile  pond.) 

Franccstown. — Soapstone,  arsenical  pyrites. 

Franconia. — Hornblende,  staurotide  !  epidote  !  zoisite,. specular  iron, 
magnetic  iron,  black  and  red  manganesian  garnets !  mispickel!  (Dana~ 
itc,)  copper  pyrites,  molybdenite. 

Gilford. — (Gunstock  mt.) — Magnetic  iron  ore,  (native  "  lodestone,") 

Goshen. — Graphite,  black  tourmaline. 

Grafton. — Mica !  (extensively  quarried,)  albite  !  asparagus  stone,  blue, 
green,  and  yellow  beryls,  tourmaline. 

Grantham. — Gray  staurotide  ! 

Hanover. — Garnet,  a  boulder  of  quartz  containing  rutile!  black  tour- 
maline, quartz. 

Haverhill. — Garnet  I  arsenical  pyrites,  native  arsenic,  galena,  blende, 
>  iron  and  copper  pyrites,  magnetic  and  white  iron  pyrites. 

Hillsboro,  (Campbell's  mountain.) — Graphite. 

Hinsdale. — Manganese  spar,  black  oxyd  of  manganese,  (photozite 
'  and  rhodonite.) 

Jackson. — Drusy  quartz,  tin  ore,  arsenical  pyrites,  native  arsenic, 


360  [LOCALITIES    OF 

fluor  spar,  apatite,  magnetic  iron  ore,  molybdenite,  wolfram,  copper 
pyrites,  arsenate  of  iron. 

Jaffrey,  (Monadnock  mt.) — Kyanite. 

Keene. — Graphite,  soapstone,  milky  quartz. 

Landaff. — Molybdenite,  lead  and  iron  ores. 

Lebanon. — Bog  iron  ore, 

Lisbon. — Staurotide,  garnets  black  and  red,  granular  magnetic  iron 
ore,  hornblende,  epidote,  zoisite,  specular  iron. 

Lyme. — Kyanite,  (N.  W.part,)  black  tourmaline, rutile,  iron  pyrites 
eopper  pyrites,  (E.  of  E,  village,)  sulphuret  of  antimony.  . 

Merrimack. — Rutile  !  (in  gneiss  nodules  in  granite  vein,) 

Moultonborough,  (Red  Hill.) — Hornblende,  bog  ore,  pyrites,  tour 
maline. 

Newport, — Molybdenite. 

Orange. — Slue  beryls  ! 

Orford. — Brown  tourmaline !  steatite,  rutile,  kyanite,  brown  iroi 
ore,  native  copper,  green  malachite,  galena, 

Pelbam. — Steatite. 

Piennont. — Micaceous  iron,  heavy  spar,  green,  white,  and  browa 
mica,  apatite. 

Richmond. — lolite  I  rutile,  soapstone,  iron  pyrites. 

Saddleback  mt. — Black  tourmaline,  garnet,  spinel. 

Sheiburne. — Argentiferous  galena,  crystalline  black  cupreous  Mendel 
copper  pyrites,  iron  pyrites,  manganese. 

Springfield — Beryls,  (very  large,  8  inches  diameter,)  manganesian 
garnets!  in  mica  slate,  albite,  mica. 

Swanzey,  (near  Keene.) — Magnetic  iron,  (in  masses  in  granite.) 

Tamworlh,  (near  White  Pond.) — Galena. 

Unity,  (estate  of  James  Neal.) — Copper  and  iron  pyrites,  chloro- 
phyllite,  green  mica,  magnetic  iron,  radiated  actinolile,  garnet,  titan- 
iferous  iron  ore,  magnetic  iron  ore. 

Walpole,  (near  Bellows  Falls.) — Made. 

Warren. — Copper  pyrites,  blende,  epidote,  quartz,  iron  pyrites,  tre- 
molite  !  galena,  rutile.,  talc,  molybdenite. 

Westmoreland. — (South  part.)  Molybdenite  !  apatite  !  blue  feldspar, 
IfOg  manganese,  (north  village,)  quartz,  Jluor  spar,  copper  pyrites,  oxyd 
of  molybdenum  and  uranium. 

White  mts.,  (notch  behind  "  old  Crawford's  house.") — Green  octahe- 
dral fluor,  quartz  crystals,  black  tourmaline,  chiastolite. 

Wilmot. — Beryl. 

Winchester. — Pyrolusite,  photozite,  diallogite,  black  oxyd  of  manga- 
nese, magnetic  iron  ore,  granular  quartz. 

VERMONT. 

Addison. — Iron  sand. 

Alburgh. — Quartz  crystals  on  calc  spar,  iron  pyrites. 

Athens. — Steatite,  rhomb  spar,  actinolite. 

Barnet. — Graphite. 

Belvidere. — Steatite,  chlorite. 

Bennington. — Pyrolusite,  brown  iron  ore,  pipe  clay,  yellow  ocher. 

Bethel. — Actinolite,  talc,  chlorite,  octahedral  iron. 

Brandon. — Braunite,  pyrolusite,  psilomelane. 


LOCALITIES    OF   MINERALS.  361 

Brattleborough. — Black  tourmaline  in  quartz. 

Bridgewater. — Talc,  dolomite,  magnetic  iron,  steatite,  chlorite, 

Bristol. — Rut&e,  brown  hematite,  manganese  ores. 

Brookfield. — Mispickel,  iron  pyrites. 

Cabot. — Garnets,  staurotide,  hornblende,  albite. 

Cavendish. — Garnet,  serpentine. 

Chester. — Asbestus. 

Chittenden. — Psilomelane,  pyroiusite,  braunite, brown  iron  ore,  specu- 
lar and  magnetic  iron,  galena. 

Colchester — Brown  iron  ore,  iron  sand,  jasper,  alum. 

Corinth. — Copper  pyrites,  magnetic  iron  pyrites, 

Coventry. — Manganese  spar. 

Dummerston. — Rutile. 

Fletcher. — Pyrites,  octahedral  iron,  acicular  tourmaline. 

Grafton. — The  steatite  quarry  is  properly  in  Athens. 

Guilford . — Scapolite . 

Jay. — Chromic  iron,  serpentine,  picrosmine,  amianthus. 

Lowell. — Picrosmine,  amianthus. 

Marlboro. — Rhomb  spar,  steatite,  garnet,  magnetic  iron. 

Mendon. — Octahedral  iron  ore, 

Middlebury. — Zircon, 

Monkton. — Pyroiusite,  brown  iron  ore. 

Moretpwn. — Smoky  quartz  !  steatite,  talc,  wad. 

Morristown. — Argentiferous  galena. 

Mount  Holly. — Asbestus,  chlorite. 

New  Fane. — Glassy  and  asbestiform  actinolite,  steatite, green  quarz, 
{called  chrysoprase  at  the  locality,)  chalcedony,  drusy  quartz,  garnet, 
•hromic  iron,  rhomb  spar. 

Norwich. — Actinolite,  feldspar,  brown  spar  in  talc. 

Pittsford. — Brown  iron  ore,  manganese  ores. 

Plymouth. — Spathic  iron,  magnetic  and  specular  iron,  both  in  octa- 
^edral  crystals. 

Plympton. — Massive  hornblende. 

Putney. — Fluor,  brown  iron  ore,  rutile,  and  zoisite  in  boulders. 

Reading. — Glassy  actinolite  in  talc. 

Readsboro'. — Glassy  actinolite,  steatite. 

Ripton. — Brown  iron  ore,  augite  in  boulders,  octahedral  iron  pyritea. 

Roxbury. — Dolomite,  talc,  serpentine,  asbestus. 

Salisbury. — Brown  iron  ore. 

Sharon. — Quartz,  kyanite. 

Shoreham. — Iron  pyrites. 

Shrewsbury. — Magnetic  iron,  and  copper  pyrites. 

Somerset. — Magnetic  iron,  native  gold. 

Stafford. — Magnetic  iron,  and  copper  pyrites,  native  copper,  horn- 
blende. 

Starksboro'. — Brown  iron  ore. 

Stirling. — Copper  pyrites,  talc,  serpentine. 

Stockbridge. — Mispickel,  magnetic  iron  ore. 

Thetford. — Blende,  galena,  kyanite. 

Troy.— Crystalline  magnetic  iron,  talc,  serpentine,  picToamine,  ami- 
*Rthus,  steatite. 

Warren. — Actinolite,  magnetic  iron  ore,  wad. 

31 


362  i  rcALiTiEs  OT 

Waterbury. — Mispickel,  copper  pyrites. 
WaterviUe. — Steatite,  actinolite,  talc. 
Westfield. — Steatite,  chromic  iron,  serpentine, 
Westminster, — Zoisite  in  bo  alders. 
Wardsboro*. — Zoisite. 
Windham. — Glassy  actinolite,  steatite. 
Woodbury. — Massive  pyrites, 
Woodstock. — Quartz  crystals. 

MASSACHUSETTS; 

Alfbrd. — Galena,  iron  pyrites. 

AthoL — Allanite,  fibrolite,  (?)  epidote  I 

Auburn. — Masonite. 

Barre. — Rutile  !  mica,  pyrites,  beryl? feldspar,  garnet. 

Great  Barrington. — Tremolite. 

Bedford.— Garnet. 

Belchertown. — -Allanite, 

Bernardston. — Magnetic  oxyd  of  iron. 

Beverly. — Polymignite,  columbite,  green  feldspar,  tin  ore, 

Blanford. — Marmolite,  schiller  spar,  serpentine,  anthophyllite,  act'i~ 
nolite  .'  chromic  iron,  kyanite,  rose  quartz  in  boulders. 

Bolton. — Scapoiite  !  petalite,  sphene,  pyroxene,  nuttalite,  diopsidef 
loltonite,  apatite,  magnesite,  rhomb  spar,  allanite,  yttrocerite,  cerium? 
ocher,  (on  the  scapolite,)  spinel. 

Boxborougb. — Scapolite,  spinel,  garnet,  augite,  aetinolite,  apatite. 

Brighton . — Asbestus. 

Brimfield,  (road  leading  to  Warren.) — lolite,  adularia,  molybdenite, 
laica,  garnet. 

CarHsle. — Tourmaline,  garnet  !  scapolite,  actinolite. 

Charleston. — Prehnite,  lawnoniie,  stilbite,,  chabazite,  quartz  crystals, 

Chelmaford. — Scapolite,  chondrodite,  blue  spinel,  amianthus  !  rose 
quartz. 

Chester. — Hornblende,  scapolite,  zoisite,  spodumene,  indicolite,  apa- 
tite— magnetic  iron  and  chromic  iron,  (west  part) — stilbite,  heulandite, 
analcirne  and  chabazite. 

Chesterfield. — Blue,  green,  and  red  tourmaline,  cleavelandite,  (al- 
bite,)  lithia  mica,  smoky  quartz, pyrochlore,  (microlite,}  spodumene,  kya- 
nite, apatite,  rose  beryl,  garnet,  quartz  crystals,  staurotide,  tin  ore, 
columbite,  variegated  copper  ore,  zoisite,  uranite. 

Conway. — Pyrolusite,  fluor  spar,  zoisite,  rutile  !!  native  alum,  galena. 

Cummington — Manganese  spar  I  cummingtonite,  white  iron  pyrites, 
garnet. 

Dedham — Asbestus,  galena. 

Deerfield. — Chabazite,  heulandite,  stilbite,  amethyst,  carnelian,  chal- 
cedony, agates. 

Fitchburg,  (Pearl  hill.) — Beryl,  staurotide  !  garnets,  molybdenite. 

Foxborough. — Iron  pyrites,  anthracite. 

Franklin . — Ame  thy  st. 

Goshen. — Lithia  mica,  albite,  spodumene  !  blue  and  green  tourma- 
line, beryl,  zoisite,  smoky  quartz,  columbite,  tin  ore,  galena. 

Hatfield. — Heavy  spar,  yellow  quartz  crystals,  galena,  blende;  yellow 
copper  pyrites. 


LOCALITIES    OF   MINERALS.  363 

fiawlcy. — Micaceous  iron,  massive  pyrites,  magnetic  iron,  zoisite. 

Heath. — Pyrites,  zoisite, 

Hinsdale. — Brown  iron  ore,  apatite,  zoisite, 

Hubbardston. — Massive  pyrites. 

Lancaster. — JKy unite,  chiastoliteJ  apatite,  staurotide,  piaite,  aa- 
«3ulusite. 

Lee. — Tremolite  !  sphene  !  (east part.) 

Lenox. — Brown  hematite,  gibbsite  (?) 

Levereit. — Heavy  spar,  galena,  blende,  copper  pyrite*. 

Leyden. — Zoisite?  rutile. 

Littleton- — Spinel,  scapolite,  apatite, 

Lynnfield- — Magnesite  on  sei^pentine. 

Martha's  Vineyard. — Brown  iron  ore,  amber*  selenite,  radiate* 
pyrites. 

Mendon. — j\lica!  chlorite. 

Middlefield. — Glassy  actinolite,  rhsmb  cpor,  steatite.,  serpentine, 
Jeldspar,  drusy  quartz,  apatite,  zoisite,  nac rite, chalcedony,  talc! 

Montague. — -Specular  iron. 

JNewbury. — Serpentine,  amianthus,  epidote^  massive  garnet,  carboa- 
aie  of  iron. 

Newburyport. — Serpentine,  nemalite,  uranite. 

,New  Braiotree. — -Black  tourmaline. 

Norwich. — Apatite  !  black  tourmaline^  fteryZ, -blende, <martz  crystals. 

Palmer,  (Three  Rivers.) — Feldspar,  prehnite,  calc  spar. 

Pelham. — Asbestus,  serpentine,  quartz  crystals,  beryl,  molybdenite, 
green  hornstone. 

PlainfiekL — Cummingtonite,  pyrolusite,  fed  manganese* 

'Richmond. — Brovon  iron  ore,  Gibbsite .'/ 

Rowe. — Epidote,  talc. 

Russel. — Schiller  spar,  (diallage  ?)  prismatic  ntiea,  -serpentine,  beryl, 
jgalena,  copper  pyrites. 

Saugus. — Porphyry. 

Sheffield, — Asbest us,  pyrites,  native  alum,  .pyrolusitt 

Shelburne. — Rutile. 

Shutesbury,  (east  of  Locke's  Pond.) — Hfoli/denite. 

Southampton. — Galena,  white  lead  ore,  anglesite,  molybdate  <rf 
lead,  fluor,  heavy  spar,  .copper  and  iron  pyrites,  blende,  corneous  lead, 
f>yromorphite. 

South  Royalston. — Beryl!!  common  mica!!  feldspar.'  ilmenite, 
allanite. 

Sterlmg. — Spodumene,  chiastolite?  spathic  iron,  mispickel,  blende, 
galena,  iron  and  copper  pyrites. 

Stoneham. — Nephrite. 

Sturbridge. — Graphite,  pyrope,  apatite,  bog  ore. 

Turner's  Falls,  (Conn.  R.) — Copper  pyrites,  prehnite,  chlorite,  chlo- 
rojihaite !  spathic  iron,  green  malachite,  magnetic  ircn  sand,  anthra- 
cite. 

Tyringham. — Pyroxene,  scapolite. 

Uxbridge. — Argentiferous  galena. 

Warwick. — Massive  garnet,  black  tourmaline,  magnetic  iron, 
epidote. 

Washing  ton, — Graphite. 


364  LOCALITIES    OF   MINERALS. 

Westfield. — Schiller  spar,  (diallage?)  serpentine,  steatite,  kyanite, 
Bcapolite,  actinolite. 

Westford. — Andalu&ite  ! 

West  Hampton. — Galena,  argentine,  pseudom&rph&us  quartz. 

West  Springfield. — Prehnite,  ankerite,  satin  spar,  celestine,  bitumin- 
ous coal. 

West  Stockbridge. — Hematite,  fibrous  pyrolusite,  spathic  iron. 

Whately. — Native  copper,  galena. 

Williamsburg. — Zoisite,  pseudomorphous  quartz,  apatite,  rose  and 
smoky  quartz,  galena,  pyrolusite,  copper  pyrites. 

Williamstown. — Cryst.  qartz. 

Windsor. — Zoisite,  actinolite,  futile  ! 

Worcester. — Mispickel,  idocrase,  pyroxene,  garnet,  amianthus,  bu- 
cholzite,  spathic  iron,  galena,  anthracite. 

Worthington. — Kyanite. 

Zoar. — Bitter  spar,  talc. 

RHODE  ISLAND. 

Bristol. — Amethyst. 

Cranston. — Actinolite  in  talc. 

Cumberland. — Manganese,  epidote,  actinolite,  garnet,  titaniferous 
iron,  magnetic  iron,  red  hematite,  copper  pyrites. 

Foster. — Kyanite  ! 

Johnson. — Talc,  brown  spar. 

Newport. — Serpentine. 

Portsmouth. — Anthracite,  graphite,  asbestus,  iron  pyrites. 

Smithfield. — Dolomite,  calc  spar,  bitter  spar,  nacrite,  nephrite,  tre- 
molite,  asbestus,  quartz,  magnetic  iron  in  chlorite  slate,  talc .'.' 

Warwick,  (Natic  village.) — Masonite,  garnets,  graphite. 

Westerly. — llmenite. 

CONNECTICUT. 

Berlin. — Heavy  spar,  datholite,  blende,  quartz  crystals. 

Bolton. — Staurotide,  copper  pyrites. 

Bradleyville,  (Litchfield.) — Laurnonite. 

Bristol. —  Vitreous  copper  .'/  copper  pyrites,  heavy  spar,  variegated 
copper  ore,  talc. 

Brookfield. — Galena,  calamine,  JZercde,  spodumene,  magnetic  pyrites. 

Canaan. — Tremolite  and  augite  .'  in  dolomite. 

Chatham. — Mispickel,  smaltine,  copper  nickel,  beryL 

Cheshire. — Heavy  spar  !  vitreous  copper,  cryst*  variegated  copper! 
green  malachite,  kaolin,  natrolite,  prehnite,  chabazite,  datholite. 

Chester. — Sillimanite  !  monazite>  epidote. 

Cornwall,  near  the  Housatonic. — Graphite,  pyroxene. 

Farmington. — Prehnite  !  chabazite,  heavy  spar,  agate,  native  copper. 

Granby. — Green  malachite. 

Greenwich. — Black  tourmaline. 

Haddam. — Chrysoberyl  !  beryl!!  epidote!!  tourmaline!  feldspar , 
anthophyllite,  garnet !  iolite  !  chlorophyllite  !  autumolite,  magnetic 
iron,  adularia,  apatite,  columbite  !  white  and  yellow  iron  pyrites,  mo- 
lybdenite !  allanitf.,  eulphuret  of  bismuth. 


XGCALITIES    OF    MINERALS. 


Hadiyme. — Ckabazite  and  stilbite  in  gneiss,  wkfa  epidote  and  garnet. 

Hartford. — Dat halite,  (Rocky  Hill  quarry.) 

Kent. — Brown  iron  or*,  pyrolusite,  ochrey  iron  ore. 

Litchfield. — Ky unite  with  corundum,  apatite  and  andaaisite,  Ilmen* 
He,  (WashingtoniteO 

Lyme. — Garnet,  sunstone. 

Meriden. — Dathoiite. 

Middlefield  Falls. — Dathoiite,  chlorite,  &c.,  in  amygdaloid. 

Middletown. — Mica,  lepidolite  with  green  and  red  tourmaline,  al- 
bite,  feldspar,  col  ambit  e  !  pre  finite,  rutile  !  beryl,  topaz,  uranite,  apa- 
tite. 

Milford. — Sahlite,  pyroxene,  ^asbestus,  zoisite,  verd-antique  marble, 
pyrites. 

New  Haven. — Serpentine,  asbestus,  chromic  iron,  safalite,  etilbite, 
prehnite. 

Norwich. — Sillimanite,  monezile .'  (edwardsite  of  Shepard,)  zircon, 
iolite,  corundum,  feldspar. 

Orange. — Pyrites. 

Oxford,  near  Humphreysville. — Kyanite, 

Roaring  Brook,  (Cheshire.) — Dathoiite!  calc spar,  preiinite,  saponite. 

Reading,  (near  the  line  of  Danbury.) — Pyroxene,  garnet. 

Roxbury. — Massive  spathic  iron,  blende. 

Salisbury. — Brown  iron  ore,  ochrey  iron,  pyrolusite  1 

Saybrook. — Molybdenite,  stilbile,  plumbago. 

Simsbury. — Vitreous  copper,  green  malachite. 

Southbury. — Rose  quartz,  Laumonite,  prehnite, 

Southington. — Heavy  spar,  datholite. 

Stafford. — Massive  pyrites, 

Stonington, — Stilbite  and  chabazitt  on  gneiss. 

Thatchersville,  (near  Bridgeport.) — Stilbite  on  gneiss,  babingtonite, 

Tolland. — Staurotide,  massive  pyrites. 

Trumbull  and  Monroe. — Chlorophane,  topaz,  beryl,  euclase  (?)  mag- 
netic pyrites,  iron  pyrites,  tungstate  of  lime,  wolfram  (pseudomorph  of 
tungsten,)  rutile,  native  bismuth,  tungstic  acid,  spathic  iron,  mispickel, 
argentiferous  galena,  blende,  scapolite,  tourmaline, garnet,  albite,  augite, 
graphic  tellurium  (?) 

Washington. — Triplite,  ilmcnitc  !  (Washingtonite  of  Shepard,)  dial- 
logite,  natrolite,  andalusite  (New  Preston,)  kyanite. 

Watertown,  near  the  the  Naugatuck. — White  sahlite,  monazite. 

West  Farms. — Asbestus. 

Winchester  and  Wilton. — Asbestus. 

NEW  YORK. 

ALBANY  Co. — Coeyman's  Landing. — Epsom  salt. 
Guilderland. — Petroleum. 
Watervliet. — Quartz  crystals. 
ALLEGANY  Co. — Cuba. — Petroleum. 
CATTAEAUGUS  Co. — Freedom. — Petroleum, 
CAYUGA  Co. — Auburn. — Fluor,  epsom  salt. 
Ludlowville. — Epsom  salt. 
Springville. — Nitrogen  springs. 
31* 


366  LOCALITIES    OF    MINERALS. 

CHATAUQUE  Co. — Fredonia. — Petroleum,  carbureted  hydrogen. 
Laona. — Petroleum. 

COLUMBIA  Co. — Ancram  Lead  Mine. — Galena,  blende,  copper pyritts, 
heavy  spar. 

Austerlitz. — Earthy  manganese,  molybdate  of  lead,  vitreous  copper. 

Hudson. — Selenite  ! 

Lebanon. — Nitrogen  Spring. 

DUTCHESS  Co. — Dover. — Garnet  (Foss  ore-bed.) 

Fishkill. — Graphite,  green  actinolite  !  talc,  hydrous  anthophyllite. 

Rhinebeck. — Granular  epidote. 

Union  Vale. — Gibbsite  (Clove  mine.) 

Amenia. — Brown  hematite. 

ESSEX  Co. — Alexandria. — Kirby's  graphite  mine,  graphite,  pyroxene, 
tcapolite,  sphene. 

Crown  Point. — Garnet,  massive  feldspar,  epidote,  epsom  salt,  apa- 
tite, (eupyrchroite  of  Emmons,}  magnetic  iron  (Peru.) 

Lewis. — Tabular  spar,  colophonite,  garnet,  labradorite. 

Long  Pond. — Apatite,  garnet,  pyroxene,  idocrase,  coccolite!!  sca- 
polite,  magnetic  iron  ore,  blue  calc  spar. 

Mclntyre. — Labradorite,  garnet,  magnet  iron  ore. 

Moriah. — Zircon !  calc  spar,  apatite,  actinolite,  (Sanford  ore-bed,) 
labradorite,  mica,  specular  iron. 

Newcomb. — Labradorite,  feldspar. 

Port  Henry. — Brown  tourmaline,  mica,  rose  quartz,  serpentine,  green 
and  black  pyroxene,  hornblende,  cryst.  pyrites,  magnetic  pyrites, 
adularia. 

Roger's  Rock. — Graphite,  tabular  spar,  garnet,  colophonite,  feldspar, 
adularia,  pyroxene,  sphene,  coccolite. 

Schroon. — Calc  spar,  pyroxene,  chondrodite. 

Ticonderoga. — Graphite,  pyroxene,  sahlite,  sphene,  black  tourmaline, 
cacoxene,  (Mt.  Defiance.) 

Westport. — Labradorite,  prehnite. 

Willsboro. — Tabular  spar,  colophonite,  garnet,  green  coccolit*,  horn- 
blende. 

FRANKLIN  Co. — Chateaugay. — Nitrogen  springs. 

Malone. — Massive  pyrites,  magnetic  iron  ore. 

GREENE  Co. — Catskill. — Calc  spar. 

Diamond  Hill. — Quartz  crystals. 

HERKIMER  Co. — Little  Falls. — Quartz  crystals,  heavy  spar,  calc  spar, 
anthracite. 

Middleville. — Quartz  crystals  !  calc  spar,  brown  and  pearl  spar. 

Salisbury. — Quartz  crystals  !  blende,  galena,  iron  and  copper  pyrites. 

Stark. — Fibrous  celestine,  gypsum. 

JEFFERSON  Co. — Antwerp. — Quartz  crystals !  serpentine  !  calc  spar, 
tpinel,  mica,  spathic  iron,  specular  iron,  arragonite,  cacoxene  I  tremo- 
lite,  fluor,  green  malachite. 

Bro  wnville . — Celestine . 

Carthage. — Cacoxene. 

Champion. — Pyrites. 

Chaumont  Bay. — Celestine. 

Depauville. — Celestine. 


LOCALITIES    OF    MINERALS.  367 

Henderson. — Mica  / 

High  Island,  (in  the  St.  Lawrence.) — Tourmaline. 
Muscolonge  Lake. — Fluor!!  mica, strontianite, idocrase. 
Natural  Bridge. — Chalcedony. 
Oxbow. — Calc  spar .'!  heavy  spar. 

Vrooman  Lake,  near  Oxbow. — Apatite  !  quartz  crystals,  cafc  war, 
pyroxene,  mica  !  tourmaline,  pyrites. 
Pillar  Point. — Massive  heavy  spar. 
Theresa. — Carbonate  of  strontia. 
Watertown. — Trcmolite. 

LEWIS  Co. — Diana,  (natural  bridge.) — Scapolite!  tabular  spar,  green 
coccolite,  feldspar,  apatite,  sj)hene,  mica,  quartz  crystals,  drusy  quartz, 
cryst.  pyrites,  magnetic  pyrites,  blue  calc  spar,  serpentine,  rensselaerite, 
zircon. 

Greig. — Magnetic  iron  ore, 

House ville. — Earthy  manganese. 

Leyden. — Calc  spar. 

Lowville. — Calc  spar,  fluor  spar,  pyrites,  galena,  blende. 

MONROE  Co. — Rochester. — Pearl  spar,  calc  spar,  snowy  gypsum, 
fluor,  celestine,  galena,  blende. 

MONTGOMERY  Co. — Root. — Pearl  spar,  drusy  quartz,  blende. 
Palatine. — Quartz  crystals,  drus}  quartz. 

NEW  YORK  Co. — Corker's  Hook.— Apatite. 

Kingsbridge. — Tremolite,  pyroxene,  mica,  tourmaline,  pyrites,  rutile. 

Harlem. — Epidote,  apophyllite,  stilbite,  tourmaline,  vivianite,  lamel- 
lar feldspar,  mica. 

New  York. — Serpentine,  amianthus,  actinolite,  talc,  pyroxene,  hy- 
drous anthophyllite,  garnet,  staurotide,  molybdenite,  graphite. 

NIAGARA  Co. — Lewiston. — Epsom  salt. 

Lockport. — Celestine  !  calc  spar,  selenite,  anhydrite,  fluor,  pearl 
spar  !  blende. 

Niagara  Falls. — Calc  spar,  fluor,  blende. 

OXEIDA  Co. — Boonville. — Calc  spar,  tabular  spar,  coccolite. 
Clinton. — Blende,  lenticular  argillaceous  iron  ore. 
ONONDAGA  Co. — Camillus.— Selenite  and  fibrous  gypsum. 
Manlius. — Gypsum  and  fluor. 
Syracuse. — Serpentine,  celestine. 

ORANGE  Co. — Cornwall. — Zircon,  chondrodite,  hornblende^  spinel, 
massive  feldspar,  fibrous  epidote,  hudsonite,  ilmenite,  serpentine, 
boltonite. 

Deer  Park. — Cryst.  pyrites,  galena. 

Monroe. — Mica  !  sphene  !  garnet,  colophonite,  epidote,  chondrodite, 
allanite,  bucholzite,  brown  spar,  boltonite,  spinel,  hornblende,  talc,  ilme- 
nite, magnetic  pyrites,  common  pyrites,  chromic  iron,  graphite. 

At  Wiiks  and  O'Neil  mine  in  Monroe. — Arragonite. 

At  Two  Ponds  in  Monroe.— Pyroxene  !  chondrodite,  hornUendet 
scapolite  !  zircon,  sphene,  apatite,  boltonite. 

At  Greenwood  Furnace. — Chondrodite, pyroxene  !  mica  !  hornblendet 
spinel,  scapolite,  mica,  ilmenite. 


368  LOCALITIES  OF  MINERALS. 

At  Forest  of  Dean. — Pyroxene,  spinel,  zircon,  scapolite,  hornblende, 
boltonite. 

Town  of  Warwick. — 

Warwick  village. — Spinel,  zircon,  serpentine  .'  brown  spar, pyroxene  ! 
hornblende  !  pseudomorphous  steatite,  feldspar  !  (Rock  Hill,)  ilmenite  t 
clintonite,  tourmaline  (R.  H.,)  rutile,  sphene,  molybdenite,  mispickel, 
white  iron  pyrites,  common  pyrites,  yellow  iron  sinter. 

Amity. — Spinel,  garnet,  scapolite,  hornblende,  idocrase,  epidote  ! 
clintonite  !  magnetic  iron  !  tourmaline,  warwickite,  apatite,  chondro- 
dite,  ilmenite,  talc,  pyroxene  !  rutile,  zircon,  corundum,  feldspar, 
sphene,  calc  spar,  serpentine,  schiller  spar.  (?) 

Edenville. — Apatite,  chondrodile  !  hair  brown  hornblende  !  tremolite, 
spinel,  tourmaline,  warwickite,  pyroxene,  sphene,  mica,  feldspar,  mis- 
pickel, orpiment,  rutile,  ilmenite,  ecorodite,  copper  pyrites. 

West  Point. — Feldspar,  mica,  scapolite,  sphene,  hornblende. 

Carmel,  (Brown's  quarry.) — Anthophyllite,  schiller  spar,  (?)  orpiment, 
mispickel. 

Cold  Spring. — Chabazite,  mica,  sphene. 

Patterson. —  White  pyroxene  !  calc  spar,  asbestus,  tremolite,  dolo- 
mite, massive  pyrites. 

Phillipstown. — Tremolite,  amianthus,  serpentine^  sphene,  diopside, 
green  coccolite,  hornblende,  scapolite,  stilbite,  mica,  laumonite,  gurhofite, 
calc  spar,  magnetic  iron,  chromic  iron. 

Phillip's  ore  bed. — Hyalite,  actinolite,  massive  pyrites. 

RENSSELAER  Co, — Hoosic. — Nitrogen  springs, 

Lansingburgh. — Epsom  salt,  quartz  crystals,  iron  pyrites. 

Troy. — Quartz  crystals,  iron  pyrites,  selenite  ! 

RICHMOND  Co. — Rossville. — Lignite,  cryst.  pyrites. 

Quarantine. — Asbestus  !  amianthus,  magnesite,  dolomite,  gurhofite, 
brucite,  serpentine,  talc, 

ROCKLAND  Co. — Caldwell. — Calc  spar  ! 

Grassy  Point. — Serpentine,  actinolite. 

Haverstraw. — Hornblende. 

Ladentown. — Zircon,  red  copper  ore,  green  malachite. 

Piermont. — Datholite,  stilbite,  apophyllite,  stellite,  prehnite,  thom- 
sonite,  nemalite,  calc  spar. 

Stony  Point. — Kerolite,  lamellar  hornblende,  asbestus. 

ST.  LAWRENCE  Co. — Canton. — Massive  pyrites,  calc  spar,  brown 
tourmaline,  sphene,  serpentine,  talc,  rensselaerite,  pyroxene,  specular 
iron,  copper  pyrites. 

Dekalb. — Hornblende,  heavy  spar,/Mor,  tremolite,  tourmaline. 

De  Long's  Mills,  in  Hammond. — Feldspar  !  pyroxene,  satin  spar, 
zircon,  apatite. 

Edwards. — Brown  and  silvery  mica  !  scapolite,  apatite,  quartz  crys~ 
tals,  actinolite,  tremolite,  specular  iron. 

Fowler. — Heavy  spar,  quartz  crystals  !  specular  iron,  blende,  galena, 
iron  and  copper  pyrites,  actinolite. 

Gouverneur. — Calc  spar  !  serpentine  !  hornblende  !  scapolite  !  feld- 
spar!! tourmaline!  pyroxene,  apatite,  rensselaerite,  sphene,  heavy 
spar,  rutile,  pseudomorphous  steatite,  black  and  copper  colored  mica, 
tremolite,  asbestus. 


LOCALITIES    OF    MINERALS.  369 

Hammond. — Apatite  V  zircon  !  feldspar,  heavy  spar,  pytites,  pur- 
ple fluor. 

Hermon. — Quartz  crystals,  specular  iron,  spathic  iron. 

Mineral  Point,  Morristown. — Fluor,  blende,  galena,  mica,  (Pope's 
Mills,  Morristown.) 

Potsdam. — Hornblende! — eight  miles  from  Potsdam  on  road  to 
Piermont  ;  feldspar  !  tourmaline,  black  mica. 

Rossie,  (Parish  ore  bed.) — Heavy  spar,  specular  iron,  coralloidal  ar- 
rngonite. 

Ros~ie  lead  mine. — Calc  spar  !!  galena  !!  pyrites  !  celestine,  copper 
pyrites,  white  lead  ore,  anglesite. 

Rossie,  (Laidlaw  Lake.) — Calc  spar,  heavy  spar,  quartz  crystals, 
chondroditej  pargasite,  pyroxene,  sphene.  Elsewhere  in  Rossie. — 
Feldspar  !  jmrgasite  !  apatite,  pyroxene,  mica,  apatite,  fluor,  serpen- 
tine, automoiiie. 

Somerville. — Chondrodite,  light  blue  spinel. 

SARATOGA  Co. — Greenfield. —  Chrysoberyl  !  garnet,  tourmaline  ! 
mica,  feldspar,  apatite,  graphite. 

SCOHARIE  Co. — Ball's  Cave,  and  others. — Calc  spar,  stalactites. 

Carlisle. — Fibrous  sulphate  of  baryta,  cryst.  and  fib.  carbonate  of 
lime. 

Scoharie. — Fibrous  celestine,  strontianite  !  cryst.  pyrites  ! 

SENECA  Co. — Canoga. — Nitrogeh  springs. 

SULLIVAN  Co. — Wurtzboro'. — Galena,  blende,  pyrites,  copper  pyritc*. 

ULSTER  Co. — Ellenville. — Galena,  blende,  copper  pyrites,  quartz. 

Marbletown. — Pyrites. 

WARREK  Co. — Caldwell. — Massive  feldspar. 

Chester. — Pyrites,  tourmaline,  rutile,  copper  pyrites. 

Diamond  Isle,  (Lake  George.) — Calc  spar,  quartz  crystals. 

Glenn's  Falls. — Rhomb  ^par. 

Johnsburg. — Fluor  !  zircon!!  graphite, serpentine, pyrites. 

WASHINGTON  Co. — Fort  Ann. — Graphite. 

Granville. — Lamellar  pyroxene,  massive  feldspar,  epidote. 

WAYNE  Co. — Wolcott.— Heavy  spar. 

WESTCHESTER  Co. — Anthony's  Nose. — Apatite,  pyrites. 

Davenport's  Neck. — Serpentine,  garnet,  sphene. 

Eastchester. — Blende,  copper  and  iron  pyrites,  dolomite. 

Hastings. — Tremolite,  white  pyroxene. 

New  Rochelle. — Serpentinf,  brucite,  magnesite,  quartz,  mica,  tremo- 
lite,  garnet. 

Peekskill. — Mica,  feldspar,  hornblende,  stilbite. 

Rye. — Serpentine,  chlorite,  black  tourmaline,  tremolite,  kerolite. 

Singsing. — Pyroxene,  tremolite,  iron  pyrites,  copper  pyrites,  beryl, 
azurite,  green  malachite,  white  lead  ore,  pyromorphite,  anglesite,  vau- 
quelinite,  galena,  native  silver. 

West  Farms. — Apatite,  tremolite,  garnet,  stilbite,  heulandite,  chaba- 
zite,  epid<5te,  sphene. 

Yonkers. — Tremolite,  apatite,  calc  spar,  analcime,  pyrites,  tour- 
maline. 

Yorktown. — Silhmanite,  monazite,  magnetic  iron. 


870  LOCALITIES    OF    MINERALS. 


NEW  JERSEY, 

Allentown,  (Monmouth  Co.) — Vivianite, 

Belville. — Copper  mines. 

Bergen. — Calc  spar,  datholite,  thomsonite,  pectolite,  (called  steilite,) 
analcime,  epistilbite,  apophyllite,  prehnite,  sphene,  stilbite,  natrolite, 
heulandite,  laumonite,  chabazite,  pyrites,  pseudomorphous  steatite  imi- 
tative of  apophyllite. 

Brunswick. — Copper  mines,  native  copper,  malachite,  mountain 
leather. 

Danville,  (Jemmy  Jump  ridge.) — Graphite,  chondrodite,  augite, 
mica. 

Flemington. — Copper  mines. 

Frank  for  t . — Serpentine . 

Franklin  and  Hamburgh,  near  the  Franklin  furnace. — Spinel !!  gar- 
net !  manganese  sjtar,  (fowlerite) !!  troostite  ! !  franklinite  ! !  red  zinc 
ore !  dysluite !  hornblende,  tremolite,  chondrodite,  white  scapolitet 
black  tourmaline,  epidote,  pink  calc  spar,  mica,  actinoHte,  augite,  sah- 
lite,  coccolite,  asbestus,  jeffersonite,  calamine,  graphite,  fluor,  beryl, 
galena,  serpentine-,  honey-colored  sphene,  quartz,  chalcedony,  amethyst, 
zircon,  molybdenite,  vivianite. 

Franklin  and  Warwick  mts. — Pyrites. 

Greenbrook. — Copper  mines. 

Griggstown- — Copper  mines. 

Imleytown. — Vivianite. 

Lockwood. — Graphite,  chondrodite,  talc,  augite,  quartz,  green 
spinel. 

Mullica  Hill,  (Gloucester  Co.) — Vivianite,  lining  belemnites. 

Newton. — Spinel,  blue  and  white  corundum,  mica,  idocrase,  horn- 
blende, tourmaline,  scapolite,  rutile,  pyrites,  talc,  calc  spar,  heavy  spar, 
pseudomorphous  steatite. 

Patterson. — Dat  halite. 

Schuyler's  mines. — Green  malachite,  red  copper  ore,  native  copper, 
chrysocolla. 

Somerville. — Red  copper  ore,  native  copper,  chrysocolla,  green  mal- 
achite, bitumen,  (two  miles  to  th£  northeast.) 

Sparta. — Chondrodite  .'  spinel,  sapphire,  green  talc,  graphite,  epidote, 
augite. 

Suckasunny,  on  the  Morris  canal. — Brown  apatite  in  magnetic 
pyrites. 

Trenton. — Zircon,  amber,  lignite. 

Vernon. — Green  spinel,  chondrodite. 

NOTE. — From  Amity.  N.  Y.,  to  Andover,  N.  J.,  a  distance  of  about 
thirty  miles,  the  outcropping  limestone,  at  different  points,  affords  more 
or  less  of  the  minerals  enumerated  as  occurring  at  Franklin.  (See  GeoL 
Rep.  on  N.  J.,  by  H.  D.  Rogers.) 

PENNSYLVANIA. 

BERKS  Co. — Morgantown. — Malachite!  chrysocolla  !  oct.  and  dodc* 
magnetic  iron,  copper  pyrites,  micaceous  iron  ore. 


LOCALITIES    OF    MINERALS.  371 

BUCKS  Co  ,  three  miles  west  of  Attleboro'. — Pyroxene,  scapolite, 
feldspar,  tabular  spar,  (a  boulder,  now  exhausted,)  zircon,  apatite,  sphene, 
green  coccolite,  graphite. — Opposite  New  Hope  in  N.  J.,  black  tour- 
maline, 

CAMBRIA  Co. — Strasberg. — Epsom  salt. 

CHESTER  Co. — Corafioidal  nrragonite.  At  London  Grove:  tremolite, 
apatite.  At  Newlin :  corundum,  beryl.  At  Phenixville  :  pearl  spar  ! 
calc  spar,  quartz  crystals,  brookite  (?)  on  quartz.  Near  Westchester :  zir- 
con, cryst.  magnesite,  amethyst,  mang.  garnet,  oxyd  of  manganese. 
South  part  of  Chester  Co. :  epidote,  magnetic  iron  ore,  rutile.  At 
Chester  Ridge  :  oxyd  of  cobalt,  hematite. 

DELAWARE  Co. — Corundum,  andalusite,  aventurine  feldspar,  ame- 
thyst, green  quartz.  At  Leiperville :  beryl  '.  black  tourmaline  !  apatite, 
garnet.  At  Concord,  Greene's  creek  :  garnet,  (pyrope  ?) !  bucholzite. 

HUNTTNGTOJT  Co. — Frankstown,  Logan's  valley,  and  near  Alexandria : 
fibrmts  celestine  ! 

LANCASTER  Co. — Anthophyllite.  At  Little  Britain :  cryst.  pyrites, 
moss  agate,  chalcedony.  At  Sadsbury  :  rutile!!  Calamine,  green  hy- 
drate of  nickel,  chromic  iron. 

MONTGOMERY  Co. — At  Perkiomen  lead  mine  :  blue  malachite,  blende, 
galena,  pyromorphite,  white  lead  ore,  molybdate  of  lead,  cupreous  sul- 
phate of  lead  1  arrglesite,  heavy  spar,  calamine. 

NORTHUMBERLAND  Co. — Opposite  Selim's  grove. — Electric  calamine. 

NORTHAMPTON  Co. — Easton. — Zircon  '.'.  (rare,)  nephrite,  saussurite  ? 
tremolite,  serpentine,  (pseudomorphic  of  calc  spar — rare,)  pyroxene, 
coccolite,  pink  carbonate  of  lime,  argillaceous  iron  ore. 

PHILADELPHIA  Co. — Near  Columbia  railroad  bridge,  on  the  Schuyl- 
kill. — Laumonite  !  (inaccessible.)  On  the  Schuylkill  road,  near  Darnley 
bridge :  kyanite.  At  Chesnut  Hill :  mica,  serpentine,  dolomite,  asbestus, 
tremolite,  nephrite,  talc,  tourmaline,  sphene.  Near  the  Wlssahiccon 
creek :  staurotide,  actinolite.  Near  Germantown :  mica,  apatite, 
(coarse.)  beryl,  feldspar. 

Near  Nicholson's  Gap,  Blue  Ridge :  blue  malachite. 

DELAWARE. 

Dixon's  quarry,  seven  miles  from  Wilmington. — Cinnamon  stone!! 
(exhausted,)  blue  apatite,  glassy  feldspar ,  sahlite,  sphene  in  pyroxene, 
kyanite. 

Brandywine  Springs. — Bucholzite,  sahlite. 

Chesapeake  and  Delaware  canal. — Eetinasphalt. 

Newcastle  Co. — Vivianite. 

MARYLAND. 

Baltimore,  (Jones  Falls,  If  miles  from  B.) — Haydenite,  heulandite, 
(beaumontite  of  Levy,)  pyrites,  fenticular  carbonate  of  iron,  mica, 
stilbite. 

Sixteen  miles  from  Baltimore,  on  the  Gunpowder. — Graphite. 

Twenty-three  miles  from  B.,  on  the  Gunpowder. —  Talc. 

Twenty-five  miles  from  B.,  on  the  Gunpowder. — Magnetic  iron, 
sphene,  pycnite. 


372  LOCALITIES    OF    MINERALS. 

Eight  to  ten  miles  north  of  B. — Brown  hematite. 

Eight  to  twenty  miles  north  of  B.,  in  limestone. — Tremolite,  augite, 
pyrites,  brown  arid  yellow  tourmaline. 

Fifteen  miles  north  of  B. — Sky-blue  chalcedony  in  granular  lime- 
stone. 

Eighteen  miles  north  of  B.,  at  Scott's  mills. — Magnetic  iron,  kyanite. 

Bare  Hills. — Chromic  iron,  asbestus,  tremolite,  talc,  hornblende,  ser- 
pentine, chalcedony,  meerschaum. 

Cape  Sable,  near  Magothy  R. — Amber,  pyrites,  alum  slate. 

Catoctin  mts. — Pyritous  copper,  carbonate  of  copper. 

Cecil  county,  north  part. — Chromic  iron  in  serpentine. 

Cooptown,  Harford  Co. — Olive-colored  tourmaline,  diallage,  talc  ot 
green,  blue,  and  rose  colors,  ligniform  asbestus,  chromic  iron,  ser- 
pentine. 

Deer  creek. — Magnetic  iron !  chlorite  slate. 

Liberty. — Specular  iron. 

Meadow  mt. — Quartz  crystals. 

Montgomery  Co. — Peroxyd  of  manganese, 

Six  miles  north  of  the  Potomac. — Chromic  iron,  in  serpentine, 
dolomite. 

Newmarket,  (between  Newmarket  and  Taneytown,  east  of  the 
Monocacey.) — Vitreous  copper,  copper  pyrites,  malachite. 

"  Soldier's  Delight." — Serpentine  (kerolite  ?)  gray  antimony. 

Somerset  and  Worcester  Cos.,  north  part. — Bog  iron  ore,  vivianite. 

St.  Mary's  river. — Gypsum !  in  clay. 

VIRGINIA  AND  DISTRICT  OF  COLUMBIA. 

Albemarle  Co.,  a  little  west  of  the  Green  mts. — Steatite,  graphite. 

AmherstCo.,  along  the  west  base  of  Buffalo  ridge. — Copper  ores,  etc. 

Buckingham  Co.,  Willis's  mt. — Kyanite,  tourmaline,  actinolite. 

Eldridge's  Gold  mine. — Gold,  auriferous  pyrites,  heavy  spar. 

Culpepper  Co.,  on  Rapidan  river. — Gold,  pyrites. 

Franklin  Co. — Grayish  steatite. 

Fauquier  Co.,  Barnet's  mills. — Asbestus. 

Phenix  copper  mines.—  Copper  pyrites,  etc. 

J.  Hood's  plantation. — Heavy  spar. 

Georgetown,  D.  C. — Rutile. 

Loudon  Co. — Tabular  quartz,  prase,  pyrites,  talc,  chlorite,  soap- 
stone,  asbestus,  chromic  iron,  actinolite,  quartz  crystals. 

Louisa  Co.,  near  Tinder's  gold  mine. — Brown  iron  ore. 

Luzerne  Co.,  Walton  gold  mine. — Gold,  pyrites,  copper  pyrites,  ar- 
gentiferous galena,  spathic  iron,  blende,  anglesite. 

Orange  Co.,  western  part,  Blue  Ridge. — Specular  Iron. 

U.  S.  Copper  Mine  District. — Vitreous  copper. 

Greenwood  gold  mines. — Gold. 

Rockbridge  Co.,  three  miles  southwest  of  Lexington. — Heavy  spar. 

Shenandoah  Co.,  near  Woodstock. — Fluor  spar. 

Mt.  Alto,  Blue  ride. — Argillaceous  iron  ore. 

Spotsylvania  Co.,  two  miles  northeast  of  Chancellorville. — Kyanite, 

Wy the  Co. ,  (Austin's  mines.) —  White  lead  ore,  minium, plumbic  ocher 
blende,  electric  calamim, galena. 


LOCALITIES    OF    MINERALS.  373 

Spotsylvania  Co.,  eighteen  miles  above  Fredericksburgh,  on  the  Rap- 
pahannock. — Gold. 

Stafford  Co.,  eight  or  ten  miles  from  Falmouth. — Micaceous  iron, 
gold,  silver,  galena,  vivianite. 

Washington  Co.,  eighteen  miles  from  Abingdon. — Rock  salt  with 
gypsum. 

Wier's  cave  and  other  caves  in  Virginia. — Calc  spar  and  stalactites. 

Kenawha. — Petroleum,  brine  springs. 

Shepardstown. — Fluor  spar, 

On  the  Potomac,  25  miles  north  of  Washington  city. — Native  sulphur 
in  gray  compact  limestone. 

NOTE. — The  minerals  usually  associated  with  the  gold  are,  arsenical 
iron,  iron  and  copper  pyrites,  carbonate  of  copper,  blende,  galena,  phos- 
phate of  lead  in  crystals,  sulphur,  peroxyd  of  iron,  and  rarely  oxyd  of 
tin  and  bismuth.  (ROGERS.) 


SOUTHERN  STATES.— NORTH  CAROLINA. 

Buncombe  Co. — Zircon !  rutile  in  quartz,  nitrogen  from  a  warm 
spring. 

Burke  Co.— Gold. 

Cabarras  Co. — Gold;  also  in  Lincoln,  Rutherford,  and  Mecklenburg 
Cos. — Phosphate  copper,  malachite. 

Chatham  Co. — Mineral  coal,  pyrites. 

Gaston  Co. — Iron  ores. 

Rutherford  Co. — Gold,  graphite,  platinum,  bismuthic  gold,  diamond, 
itacolumite  ;  on  the  road  to  Cooper's  gap. — Kyanite. 

Davidson  Co.,  (King's  mine.) — Lamellar  native  silver,  carbonate  of 
lead!  pyromorphite !  galena,  blende,  malachite,  black  copper,  oxyd  of 
tin  and  manganese.  

At  Conrad  Hill,  five  miles  from  King's  mine. — Gold,  copper  ores. 

Lincoln  Co.,  near  Crowder's  mountain. — Gold,  iron  ores,  lazulite, 
kyanite,  garnet,  graphite. 

Stokes  and  Surrey  Cos. — Iron  ores,  graphite. 

Yancey  Co. — Iron  ores,  amianthus. 

SOUTH  CAROLINA. 

Abbeville  Dist. — Gold,  galena,  phosphate  oflead. 

Anderson  Dist. — Galena. 

Cheowee  Valley. — Galena,  tourmaline,  gold. 

Chesterfield  Dist. — Gold,  (Brewer's  mine,)  talc,  pyrites,  native  bis- 
muth, oxyd  of  bismuth,  red  and  yellow  ocher,  whetstone. 

Greenville  Dist. — Galena,  phosphate  oflead,  kaolin. 

Lancaster  Dist. — Gold,  (Hale's  mine,! talc,  pyrites;  also  at  Black- 
man's  mine,  Massey's  mine,  Ezell's  mine. 

Picken's  Dist  — Gold,  manganese  ores,  kaolin. 

Spartanburg  Dist. — Magnetic  iron  ore;  at  the  Cowpens — brown 
hematite,  graphite,  limestone,  copperas. 

Union  Dist. — Fairforest  gold  mines,  pyrites,  copper  pyrites. 

York. — Limestone,  whetstones. 
32 


374  LOCALITIES   OF   MINERALS. 


GEORGIA. 

Burke  and  Scriven  Cos.— Hyalite. 

Habersham  Co. — Gold,  iron  and  copper  py rites,  galena,  hornblende, 
garnet,  quartz,  kaolin,  soapstone,  chlorite,  rutile,  iron  ores,  galena,  tour- 
maline, staurotide,  zircon. 

Hall  Co. — Gold,  quartz,  kaolin,  diamond. 

Hancock  Co. — 'Agate,  chalcedony. 

Lumpkin  Co. — Gold,  quartz  crystals. 

Rabun  Co. — Gold,  copper  pyrites. 

ALABAMA. 

Centerville. — Iron  ores,  marble,  heavy  spary  coal,  cobalt. 
Tuscaloosa  Co. — Coal,  galena. 

FLORIDA. 

Near  Tampa  bay. — Limestone,  sulphur  springs,  chalcedony,  carnc- 
lian,  agate,  siiicified  shells  and  corals. 

WESTERN  STATES.— OHIO. 

Bainbridge,  (Copperas  mt.,  a  few  miles  east  of  B.) — Calc  spar,  heavy 
spar,  iron  pyrites,  copperas,  alum. 

Canfield. — Gypsum  ! 

Duck  creek,  Monroe  Co. — Petroleum. 

Liverpool. — Petroleum. 

Marietta. — Argillaceous  iron  ore  ;  iron  ore  abundant  also  in  Scioto 
and  Lawrence  Cos. 

Poland. — Gypsum  ! 

ARKANSAS. 

Ouachita  springs. — Quartz  !  whetstones. 

Magnet  Cove. — Arkansite,  ozarkite,  schorlomite,  elaolite,  magnetic 
iron,  quartz,  green  coccolite. 

MICHIGAN. 

Lake  Superior  mining  region. — Native  copper  !  silver  !  copper  pyr- 
ites, black  oxyd  of  copper,  (at  Copper  Harbor,)  horn  silver,  gray  copper, 
manganese  ores,  prehnite,  datholite,  (large  vein  on  W.  point  of  Eagle 
harbor,)  stilbite,  laumonite,  analcime,  tabular  spar,  calc  spar ;  galena 
and  sulphuret  of  copper  on  Chocolate  river  ;  copper  pyrites  and  native 
copper  at  Presqu'  Isle. 

Isle  Royal. — Copper  ores. 

.  ILLINOIS. 

Gallatin  Co.,  on  a  branch  of  Grand  Pierre  creek,  16  to  30  miles  from 
Shawneetown,  down  the  Ohio,  and  from  3  to  8  miles  from  this  river. — 
Violet  fluor  spar  .'  heavy  spar,  galena,  blende,  brown  iron  ore. 

In  Northern  Illinois,  townships  27,  28,  29,  several  important  mines 
of  galena. 


LOCALITIES    OF    MINERALS.  375 


INDIANA. 

Limestone  caverns. — Epsom  salt;  in  most  of  the  S.  W.  counties 
pyrites,  sulphate  of  iron,  and  feather  alum;  on  Sugar  creek,  pyrites 
and  sulphate  of  iron!;  in  sandstone  of  Floyd  Co.,  near  the  Ohio. 
gypsum  ;  at  the  top  of  the  blue  limestone  formation,  brown  spar  .'  calc 
spur. 

WISCONSIN 

At  Mineral  Point  and  elsewhere,  copper  and  lead  ores  abundant, 
principally  silicate  and  carbonate  of  copper  and  galena.  Also  pyrites, 
capillary  pyrites,  blende,  white  lead  ore,  leadhiilite,  calamine,  angle- 
site,  heavy  spar,  and  calc  spar  ;  often  in  highly  interesting  forms. 

IOWA. 

Du  Buque  lead  mines,  and  elsewhere. — Galena  !  calc  spar,  black 
ozyd  of  manganese  ;  at  Swing's  and  Sherard's  diggings,  calamine  !  ; 
at  Des  Mains,  quartz  crystals  ;  Mahoqueta  R.,  brown  iron  ore. 

MISSOURI. 

Jefferson  Co.,  at  Valle's  diggings. — Calamine,  galena,  white  lead  ore, 
anglesite,  pyritous  copper,  blue  and  green  malachite,  carbonate  of 
baryta. 

Mine  a  Burton. — Galena,  white  lead  ore,  anglesite,  heavy  spar,  calc 
spar. 

Deep  Diggings. — Carbonate  of  copper,  white  lead  ore  in  crystals,  and 
manganese  ore. 

Mine  La  Motte. — Galena  !  malachite,  earthy  cobalt  and  nickel,  bog 
manganese,  sulphuret  of  iron  and  nickel,  white  lead  ore  in  crystals,  cora- 
cite,  caledonite,  plumbo-resinite,  wolfram. 

Perry's  Diggings,  and  elsewhere. — Galena,  etc. 

Forty  miles  west  of  the  Mississippi  and  ninety  south  of  St.  Louis,  the 
iron  mountains,  specular  iron,  brown  hematite. 

KENTUCKY. 

Mammoth  cave. — Gypsum  in  imitative  forms,  stalactites,  niter,  epsom 

salt. 

TENNESSEE. 

Brown's  creek. — Galena,  blende,  heavy  spar,  celestine. 

Carter  Co.,  foot  of  Roan  mt. — Sahlite,  magnetic  iron. 

Claiborne  Co. — Calamine,  galena,  electric  calamine,  chlorite,  steatite, 
and  magnetic  iron. 

Cocke  Co.,  near  Brush  creek. — Cacoxene,  kraurite,  iron  sinter,  stilp- 
nosiderite,  brown  hematite. 

Davidson  Co. — Selenite  with  granular  and  snowy  gypsum,  or  alabas- 
ter, crystallized  and  compact  anhydrite,  fluor  in  crystals !  calc  spar  in 
crystals.  Near  Nashville,  blue  celestine,  (crystallized,  fibrous  and  radi- 
ated,) with  heavy  spar  in  limestone.  Haysboro,  galena,  blende,  with 
heavy  spar  as  the  gangue  of  the  ore. 


376  LOCALITIES    OF    MINERALS. 

Dickson  Co. — Manganite. 

Jefferson  Co. — Calamine,  galena,  fetid  heavy  spar. 

Knox  Co. — Magnesian  limestone. 

Maury  Co. — Wavellite  in  limestone. 

Morgan  Co. — Epsom  salt,  nitrate  of  lime. 

Roan  Co.,  eastern  declivity  of  Cumberland  mts. — Wavellite  in  lime- 
stone. 

Severn  Co.,  in  caverns. — Epsom  salt,  soda,  alum,  saltpeter,  nitrate 
of  lime. 

Smith  Co  —Fluor. 

White  Co.,  Sp*arta,  about  the  Calf  Killer's  creek. — A  rolled  fragment 
of  sulphuret  of  silver,  fluor,  liquid  bitumen. 

Stone  creek,  near  Mr.  Holland's. — Iron  ore,  black  oxyd  of  manganese. 

Smoky  int.,  on  declivity. — Hornblende,  garnet,  staurotide. 


FOREIGN    MIXING    REGION*.  3T7 


BRIEF  NOTICE  OF  FOREIGN  MINING  REGIONS. 

The  geographical  positions  of  the  different  mining  re- 
gions are  learned  with  difficulty  from  the  scattered  notices 
in  the  course  of  a  mineralogical  treatise.  A  general  review 
of  the  more  important  is  therefore  here  given,  to  be  used 
in  connection  with  a  good  map. 

A  course  across  Europe  from  southeast  to  northwest,  passes 
over  a  large  part  of  the  mining  regions,  and  it  will  be  found 
most  convenient  to  the  memory  to  mention  them  in  this  or- 
der,  commencing  with  the  borders  of  Turkey. 

1.  The  mines  of  the  Bannat  in  southern  Hungary,  near 
the  borders  of  Turkey,  (about  latitude  45  )  situated  princi- 
pally at  Orawitza,  Saszka,  Dognaszka,  and  Moldawa.     Ores. 
Argentiferous  copper  ores,  vitreous  copper,  malachite,  copper 
pyrites,  red  copper  ore,  galena,  ores  of  zinc,  cobalt,  native 
gold,  yielding  silver,  gold,  copper,  and  lead.     Rock.    Syenite, 
and  granular  limestone. 

2.  The  mines  of  western   Transylvania,  about  latitude 
46  ,  situated  between  the  rivers  M aros  and  Aranyos,  at  Nagy- 
ag,  Offenbanya,    Salathna,    and   Vorospatak.     Ores.     Na- 
tive gold,  telluric  gold,  telluric  silver,  white  tellurium,  with 
galena,  blende,  orpiment,  realgar,  gray  antimony,   fahlerz, 
carbonate  of  manganese,  manganblende  ;  especially  valua- 
ble in  gold  and  silver. 

3.  In  the    mountain  range,  bounding  Transylvania  on 
the  north,  about  latitude  47°  40 ,  at  Nagy-banya,  Felso-ban- 
ya,  and  Kapnik.     Ores.     Native  gold,  red  silver,  argentife- 
rous gray  copper,  pyritous  copper,  blende,  realgar,  gray  an- 
timony.    Rock.     Porphyry. 

4.  In  the  Konigsberg  mountains,  northern  Hungary,  about 
latitude  48°  45,  at  Schemnitz  and  Kremnitz.     Ores.     Ar- 
gentiferous galena  and  copper  pyrites,  native  gold,  red  silver 
ore,  gray  antimony,  some  cobalt  ores  and  bismuth,  mispickel ; 
particularly  valuable  for  gold,  silver,  and  antimony.     Rock. 
Diorite  and  porphyry. 

5.  To  the  east  of  the  Konigsberg  mountains,  at  Schmol- 
nitz  and  Retzbanya.     Ores.     Pyritous  copper,  gray  copper 
ore,  blende,  gray  antimony,  particularly  valuable  for  copper. 
Rock.     Clay  slate. 

6.  Illyria,  west  of  Hungary,  at  Bleiberg  and  Raibel,  (in 
Carinthia.)     Ores.     Argentiferous   galena,   calamine,  with 

32* 


378  FOREIGN   MINING    REGIONS. 

some  copper  pyrites  and  other  ores,  affording  silver  and 
zinc  abundantly.  Rock.  Mountain  limestone. — Alsoatldria, 
native  mercury  and  cinnabar,  in  argillaceous  schist. 

7.  In  Western  Styria,  at  Schladming.     Ores.     Arsenical 
nickel,  copper  nickel,  native  arsenic,  arsenical  iron,  largely 
worked  for  nickel.     Rock.     Argillaceous  slate.      Illyria  and 
Styria  are  noted  also  for  their  iron  ores,  especially  spathic  iron. 

8.  In  the  Tyrol,  at   Zell.     Ores.     Argentiferous  copper 
and  iron  ores,  auriferous  pyrites,  native  gold.     Rock.     Ar- 
gillaceous slate. 

9.  In  the  Erzgebirge  separating  Bohemia  from  Saxony, 
and  consisting  principally  of  gneiss. 

A.  Bohemian  or  southern   slope,  at  Joachimstahl,  Mies, 
Schlackenwald,  Zinnwald,  Bleistadt,  Przibram,  Katherinen- 
berg.     Ores.     Tin  ores,  argentiferous  galena,  (worked  prin- 
cipally for  silver,)  arsenical  cobalt  ores,  copper  nickel,  af- 
fording tin,  silver,  cobalt,  nickel,  and  arsenic. 

B.  Saxon  or  northern  slope,  at  Altenberg,  Geyer,  Marien- 
berg,    Annaberg,   Schneeberg,    Ehrenfriedersdorf,    Johann- 
georgenstadt,  Freiberg.   Ores.  Argentiferous  galena,  (worked 
only  for  silver,)  tin  ore,  various  cobalt  and  nickel  ores,  vi- 
treous and  pyritous  copper,  affording  silver,  tin,  cobalt,  nickel, 
bismuth,  and  copper. 

10.  In  Silesia,  in  the  Riesen-gebirge,  an  eastern  extension 
of  the  Erz-gebirge,   at  Kupferberg,    Jauer,    Reichenstern. 
Ores  of  copper,  cobalt,  affording  copper,  cobalt,  arsenic  and 
sulphur. 

11.  In  Silesia,  in  the  low  country  east  of  the  Riesen-ge- 
birge, near  the  boundary  of  Poland,  at  Tarnowitz.     Ores. 
Calamine,  electric  calamine,  blende,  argentiferous  galena, 
affording  zinc,  silver  and  lead.     Rock.     Mountain  limestone. 

12.  Northwest  of  Saxony,  near  latitude  51°  30',  at  Eisle- 
ben,  Gerlstadt,  Sangerhausen,  and  Mansfeld.      Ores.    Gray 
copper,  somewhat  argentiferous,  variegated  copper  ore,  af- 
fording copper.     Rock.     A  marly  bituminous  schist  (kupfer- 
schiefer)  more  recent  than  the  coal  strata. 

13.  In  the  Harz-gebirge,  (Hartz  mountains,)  north  of  west 
from  Eisleben,  about  latitude  51°  50',  at  Clausthal,  Zeller- 
feld,  Lauthenthal,  Wildemann,  Grund,  Andreasberg,  Goslar, 
Lauterberg.     Ores.     Vitreous  copper,  gray  copper,  pyritous 
copper,  cobalt  ores,  copper  nickel,  ruby  silver  ore,  argentif- 
erous galena,  blende,  antimony  ores,  affording  silver,  lead, 
copper,  and  some  gold. 


FOREIGN    MINING    REGIONS.  379 

14.  In  Hesse-Cassel  to  the   southwest  of  the  Hartz,  at 
Riechelsdorf.       Ores.      Arsenical  cobalt,   arsenical  nickel, 
nickel  ocher,  native    bismuth,  bismuth  glance,  galena,   af- 
fording cobalt.     Rock.     Red   sandstone.     Also   at  Bieber, 
cobalt  ores  in  mica  slate. 

15.  In  the  Bavarian  or  Upper  Rhine,  (Palatinate,)  near 
latitude  49°  45 ,  at  Landsberg  near  Moschel,  Wolfstein,  and 
Morsfeld.      Ores.    Cinnabar,  native  mercury,  amalgam,  horn 
quicksilver,  pyrites,  brown  iron  ore,  some  gray  copper  ore, 
and  copper  pyrites.     Rocks.     Coal  formation. 

16.  Province   of  the  Lower  Rhine,   at  Altenberg,  near 
Aix  la  Chapelle  (or  Aachen.)     Ores.     Calamine,  electric 
calamine,  galena,  affording  zinc.     Rock.     Limestone.     The 
same,  just  south  in  Netherlands,  at  Limburg,  and  also  to  the 
west  at  Vedrin,  near  Namur. 

17.  There  are  also  copper  mines  at  Saalfeld,  west  of  Sax- 
ony,  in    Saxon-Meiningen,    in    Southern    Westphalia  near 
Siegen,  in  Nassau  at  DilfenKerg,  and  elsewhere. 

18.  In  Switzerland,  Canton  du  Valais.     Ores.     Argentif- 
erous lead,  and  valuable  nickel  and  cobalt  ores. 

19.  The  range  of  the  Verges,  in  France,  parallel  with 
the  Rhine,  about  St.  Marie-aux-Mines.     Ores.     Argentifer- 
ous galena,  (affording  1-1000  of  silver,)  with  phosphate  of 
lead,  gray  copper,  antimonial  sulphuret  of  silver,  native  sil- 
ver, arsenical  cobalt,  native  arsenic,  and  pyrites,  occasion- 
ally auriferous  ;  affording  silver  and  lead.     Rocks.     Argil- 
laceous schist,  syenite,  and  porphyry. 

20.  In  France  there  are  also  the  mining  districts  of  the 
Alps,  Auvergne  or  the   Plateau   of  Central  France,    Brit- 
tany, and  the  Pyrenees,  but  none  are  very  productive,  ex- 
cept in  iron  ores.     Brittany  resembles  Cornwall,  and  for- 
merly yielded  some  tin  and  copper.     The  valley  of  Oisans 
in  the  Alps,   at   Allemont,   contains   argentiferous   galena, 
arsenical  cobalt  and  nickel,  gray  copper,  native  mercury,  and 
other  ores,  in  talcose,  micaceous,  and  syenitic  schists,  but 
they  are  not  now  explored.     The  region  of  Central  Fiance 
is  worked  at  this  time  only  at  Pont-Gibaud,  in  the  department 
of  Puy-de-Dome,  and  at  Vialas  and  Villefort  in  the  Gard. 
The  former  is  a  region  of  schistose  and  granite  rocks,  inter- 
sected by  porphyry,  affording  some  copper,  antimony,  lead,  and 
silver ;  the  latter  of  gneiss,  affording  lead  and  silver,  from 
argentiferous  galena.     The  French  Pyrenees  are  worked  at 
the  present  time  only  for  iron. 


380  FOREIGN    MINING    REGIONS. 

21.  In   England  there    are  two  great  metalliferous  dis- 
tricts. 

A.  On  the   southwest,  in    Cornwall,   and   the   adjoining 
county  of  Devonshire.     Ores.     Pyritous  copper  and  various 
other  copper  ores,  tin  ore,  galena,  with  some  bismuth,  co- 
balt, nickel,  and  antimony  ores,  affording  principally  copper, 
tin,  and  lead.     Rocks.     Granite,  gneiss,  micaceous  and  ar- 
gillaceous schist. 

B.  On  the  North,  in  Cumberland,  the  adjoining  parts  of 
Durham,  with  Yorkshire  and  Derbyshire,  just  south.     Ores. 
Galena,  and  other  lead  ores,  blende,  copper  ores,  calamine, 
(the   last   especially   at    Alstonmoor    in    Cumberland,    and 
Castleton  and  Matlock,  in  Derbyshire,)  affording  largely  of 
zinc,  and  three-fifths  of  the  lead  of  Great  Britain,  and  some 
copper.     Rock.     Carboniferous  limestone. 

C.  There  is  also  a  rich  vein  of  calamine,  blende,  and  ga- 
lena, in  the  same  limestone  at  Holywell,  in  Flintshire,  on 
the  north  of  Wales  ;  another  of  calamine  at  Mendip  Hills, 
in  Southern  England,  south  of  the  Bristol  channel,  in  Som- 
ersetshire, occurring    in    magnesian    limestone  ;  mines    of 
copper  on  the  isle  of  Anglesey,  in  North  Wales,  in  Westmore- 
land and  the  adjacent  parts  of  Cumberland  and  Lancashire, 
in  the  southwest  of  Scotland,  the  Isle  of  Man,  and  at  Ecton 
in  Staffordshire,  &c. 

22.  In  Spain,  there  are  mines — 

A.  On  the  south,  in  the  mountains  near  the  Mediterranean 
coast,  in  New  Grenada,  and  east  to  Carthagena,  in  Murcia  ; 
situated  in  New  Grenada,  in  the  Sierra  Nevada,  or  the  moun- 
tains of  Alpujarras,  the  Sierra  Almagrera,  the  Sierra  de  Ga- 
dor,  just  back  of  Almeria,  and  at  Almazarron  near  Cartha- 
gena.    Ore.     Galena,  which  is  argentiferous  at  the  Sierra 
Almagrera,  and  at  Almazarron,  affording  full  1  per  cent,  of 
silver.     Rock.     Limestone,  associated  with  schist  and  crys- 
talline rocks. 

B.  The  vicinity  of  the  range  of  mountains  running  west- 
ward from  Alcaraz,  (in  the  district  of  La  Mancha,)  to  Por- 
tugal.    1.  On  the  south,  near  the  center  of  the  district  of 
Jaen,  at  Linares,  latitude  38°  5',  longitude  3°  40 .     Ores. 
Galena,  carbonate   of  lead,  red  copper  ore,  malachite,   in 
granite  and  schists  ;  affording  lead  and  copper.     2.     In  La 
Mancha,  at  Alcaraz,  northeast  of  Linares,  latitude  38°  45'. 
Ores.     Calamine    affording    abundantly    zinc.      3.    In    the 
west  extremity  of  La  Mancha,   near  latitude    38°   38',   at 


FOREIGN    MINING    REGIONS.  381 

Almaden.  Ores.  Cinnabar,  native  mercury,  horn  quicksil- 
ver, pyrites,  in  clay  slate.  4.  Southwest  of  Almaden,  in 
Southern  Estremadura,  and  Northwestern  Sevilla,  at  Guadal- 
canal, Cazalla,  Rio  Tinto.  Ores.  Gray  copper,  copper 
vitriol,  malachite,  with  some  red  silver  ore,  and  native  silver, 
in  ancient  schists  or  limestones. 

There  are  also  mines  of  lead  and  copper  at  Falsete  in 
Catalonia ;  in  Galicia,  a  little  tin  ore ;  in  the  Asturias  at 
Cabrales,  copper  ores. 

23.  In  Sweden  : — 1.    At  Fahlun,  in  Dalecarlia.     Ores. 
Copper   pyrites,    variegated    copper.     Rock.     Syenite    and 
schists. — At  Finbo  and  Broddbo.     Ores.     Columbium  ores, 
tin  ore. — At  Sala.     Ore.     Argentiferous  galena,  affording 
lead  and  silver.     Rock.     Crystalline  limestone. — At  Vena, 
(or  Wehna,)  and  at  Tunaberg.     Ores.     Arsenical  cobalt, 
arsenate  of  cobalt.     Rock.    Mica  slate  and  gneiss. — At  Dan. 
nemora  and  elsewhere.     Ore.     Magnetic  iron. 

24.  In  Norway,  at  Kongsberg,  vitreous  silver,  native  sil- 
ver, horn  silver,  native  gold,  galena,  native  arsenic,  blende. 
Rock.     Mica  slate. — At  Modum  and  Skutterud.     Ores.    Co- 
balt ores,  native  silver.     Rock.     Mica  slate. — At  Arendal, 
magnetic  iron. 

25.  In  Russia  : — 1.  In  the  Urals,  (mostly  on  the  Asiatic 
side,)  at  Ekatherinenberg,  Beresof,  Nischne  Tagilsk,  &c. 
Ores.    Native  gold,  platinum,  iridium,  native  copper,  red  oxyd 
of  copper,  malachite.     2.  The  Altai,  (southern  Siberia,)  at 
Kolyvan  and  Zmeof.     Ores.     Native  gold,  native  silver,  ar- 
gentiferous galena,  carbonate  of  lead,  native  copper,  oxyds 
of  copper,  malachite,   pyritous    copper,    calamine.     Rocks. 
Metamorphic  beds,  and  porphyry.     3.  In  the  Daouria  moun- 
tains, east  of  Lake  Baikal,  at  Nertchinsk.     Ores.     Argen- 
tiferous galena,  carbonate  of  lead,  arsenate  of  lead,  gray  an- 
timony, arsenical  iron,  electric  calamine,  cinnabar.     Rocks. 
Ancient  compact  limestone  and  schists. 

Other  important  foreign  mines,  are  the  copper  mines  of 
Cuba,  South  America,  Southern  Australia  ;  the  silver  mines 
of  South  America  and  Mexico ;  the  gold  mines  of  South 
America,  Africa,  and  the  East  Indies  ;  the  quicksilver  mines 
of  Huanca  Velica,  Peru,  and  those  of  China  ;  the  tin  of 
Malacca,  (principally  on  the  island  of  Junck  Ceylon,)  of 
Banca ;  of  zinc,  in  China ;  of  platinum,  in  Brazil,  Colum- 
bia, St.  Domingo,  and  Borneo ;  of  palladium,  in  Brazil ;  of 


382  MINERALOGICAL    INSTRUMENTS. 

arsenic  in  Khoordistan,  China.     Copper  mines  are  also  re- 
ported from  New  Zealand. 

MINERALOGICAL  IMPLEMENTS. 

f     For  the  examination  and  collection  of  minerals,  the  min- 
eralogist should  be  provided  with  a  few  simple  implements. 

1.  A  three-cornered  or  small  flat  file,  for  testing  hardness. 

2.  A  knife  with  a  pointed  blade,  of  good  steel,  for  trying 
hardness.     Berzelius  suggests  that  it  may  be  magnetized,  to 
be  used  as  a  magnet. 

3.  The  series  of  crystallized  minerals,    constituting   the 
scale  of  hardness    (see  page  64.)     The  diamond  and  talc 
are  least  essential. 

4.  Small  glass-stoppered  bottles  (one-ounce)  of  each  of  the 
acids  muriatic,  sulphuric,  and  nitric,  in  a  dilute  state,  (page 
66.) 

5.  A  blowpipe,  (page  67.) 

6.  The  common  fluxes,  (page  69.) 

7.  Pieces  of  charcoal  for  blowpipe  purposes,  (page  69.) 
Also  strips  of  mica  for  holding  the  assay  when  platinum  is 
not  at  hand. 

8.  A  candle  or  lamp  for  blowpipe  trials,  (page  68.) 

9.  Platinum  foil,  wire,  and  forceps,  (page  69.) 

10.  Also  a  pair  of  small  steel  spring  forceps,  for  holding 
fragments  of  minerals  in  the  blowpipe  flame,  and  for  man- 
aging the  assay. 

11.  A  piece  of  glass  tube,  £  inch  bore  ;  and  two  or  three 
test  tubes  (of  hard  glass,)  or  small  mattresses,  for  trying  the 
action  of  acids,  and  testing  the  presence   of  water  by  the 
blowpipe. 

12.  A  pair  of  cutting  pliers,  for  removing  chips  of  a  min- 
eral for  blowpipe  or  chemical  assay. 

13.  A  common  goniometer  ;  or  a  pair  of  arms  pivoted  to- 
gether to  use  with  a  scale,  as  explained  on  pages  47,  48. 
The  reflecting  goniometer  (page  50)  is  also  a  desirable  in- 
strument. 

14.  Models  of  the  common  crystalline  forms  ;  they  may 
be  made  by  the  student,  out  of  chalk,  or  wood  ;  and  when 
finished,  a  coat  of  varnish  or  gum  will  give  great  hardness 
to  the  chalk. 

15.  A  pair  of  balances  for  specific  gravity,  (page  63.) 

16.  A  hammer  weighing  about  two  pounds,  resembling  a 


MINEHALOGICAL    IMPLEMENTS.  383 

stone  cutter's  hammer,  having  a 

slightly    rounded    face,   and    at 

the  opposite  end,  an  edge  hav-l 

ing  the  same  direction  as   the  I 

handle.     The  handle  should  be 

made  of  the  best  hickory,  and  the  mortice  to  receive  it 

should  be  as  large  as  the  handle. 

17.  Another  hammer  of  half  a  pound  weight,  similar  to 
the  preceding,  except  that  the  face  should  be  flat ;  to  be  used 
in  trimming  specimens. 

18.  A  small  jeweller's  hammer,  for  trying  the  malleabili- 
ty of  globules  obtained  by  the  blowpipe,  and  for  other  pur- 
poses. 

19.  A  piece  of  steel,  say  £  inch  thick,  1  or  2  wide,  and  2 
or  3  long,  to  be  used  as  an  anvil.     A  fragment  may  be  broken 
or  pulverized  upon  it,  by  first  folding  it  in  a  piece  of  thin  pa- 
per, to  prevent  its  flying  oil'  when  struck.     A  half  inch  cir- 
cular cavity  on  one  side,  and  a  pestle  to  correspond,  will  be 
found  very  convenient. 

20.  Two  steel  chisels  of  the  form  of  a  wedge,  as  in  the 
annexed  figure  ;  one  6  inches  long,  and  the  other  3.     When 
it  is  desired  to  pry  open  seams  in  rocks  with  the  larger 
chisel,  two  pieces  of  steel  plate  should  be  provided  to 
place  on  opposite  sides  of  the    chisel,  after  an  opening 

is  obtained  ;    this  protects  the  chisel  and  diminishes 
friction  -while  driving  it. 

21.  Bone  ashes,  to  be  used  upon  mica,  or  in  a  small  cav- 
ity in  charcoal,  in  cupelling  for  silver,  with  the  blowpipe. 
A  rounded  cavity  should  be  made  in  the  charcoal,  as  large 
as  the  end  of  the  little  finger,  and  the  bone  ashes  (slightly 
moistened,  and  mixed  with  a  little  soda,)  should  be  pressed 
into  it  firmly  with  the  head  of  a  small  pestle  ;   after  tho- 
roughly drying,  it  is  in  a  condition  to  receive  the  assay. 

22.  A  pocket  microscope. 

23.  A  small  agate  mortar  and  pestle. 

24.  A  magnetic  needle. 

25.  A  pair  of  scissors. 

26.  A  box  of  matches. 

For  blasting  and  other  heavy  work,  the  following  tools 
and  appliances  are  necessary  : — 

1.  Three  hand-drills,  18,  24,  and  36  inches  long,  an  inch 
in  diameter.  The  best  form  is  a  square  bar  of  steel,  with 
a  diagonal  edge  at  one  end.  The  three  are  designed  to  fol- 
low one  another. 


V 


384  WEIGHTS,    MEASUKES,    AND   COINS. 

2.  A  sledge  hammer  of  6  or  8  pounds  weight,  to  use  in 
driving  the  drill. 

3.  A  sledge  hammer  of  10  or  12  pounds  weight,  for  break- 
ing  up  the  blasted  rock. 

4.  A  round  iron  spoon,  at  the  end  of  a  wire   15  or  18 
inches  long,  for  removing  the  pulverized  rock  from  the  drill- 
hole. 

5.  A  crowbar,  a  pickaxe,  and  a  hoe,  for  removing  stones 
and  earth  before  or  after  blasting. 

6.  Cartridges  of  blasting  powder,  to  use   in  wet  holes'. 
They  should  one-third  fill  the  drill-hole.     After  the  charge 
is  put  in,  the   hole   should  be  filled  with   sand  and  gravel 
alone  without  ramming.     If  any  ramming  material  is  used, 
plaster  of  Paris  is  the  best,  which  has  been  wet  and  after- 
wards  scraped  to  a  powder. 

7.  Patent  fuse  for  slow  match,  to  be  inserted  in  the  car- 
tridge, and  to  lead  out  of  the  drill-hole. 


WEIGHTS,  MEASURES,  AND  COINS. 

For  the  convenience  of  the  student,  the  following  infor- 
mation is  here  inserted,  of  such  weights,  measures,  and 
coins,  of  different  countries,  as  are  likely  to  be  met  with  in 
the  course  of  his  ordinary  reading  on  minerals  and  mining. 

24  grains,  Troy,  =  1  pennyweight  (dwt.) 

20  dwt.          "  =1  ounce  (oz.) 

12  oz.  "  =  1  pound  (Ib.) 

16  drams  Avoirdupois,  =  1  oz. 

16  oz.  "  =1  pound. 

112  Ibs.          "  =  1  hundred  (c\vt.) 

20  cwt.  "  =1  ton. 

1  Ib.  troy  =  5760  grs.  troy  =  13  oz.  2-65143  drams  av. 
1  Ib.  av.  =  7000  grs.  troy  =  1  Ib.  2  oz.  1  dwt.  16  gr.  troy. 

To  reduce  pounds  troy,  to  pounds  avoirdupois,  multiply  by 
the  decimal  .822857  ,•  or,  approximately,  diminish  by  3-17. 

To  reduce  pounds  avoirdupois,  to  pounds  troy,  multiply  by 
1-215. 

100  Ibs.  av.  is  now  the  usual  1  cwt.,  and  25  Ibs.  the  quar- 
ter cwt. 

112  pounds,  formerly  =  1  quintal. 

100  pounds,  now  usually         =  1  quintal. 
1  French  gramme  =  15-433159  grs.  troy. 


WEIGHTS,    MEASURES,    AND    COINS.  385 

1  French  kilogramme  =  1000  grammes  ••=  2'21  Ibs.  av. 
nearly  =»  2-68  Ibs.  troy  =  2-0429  French  lirres. 

To  reduce  Approximately. 

Fr.  kilograms  to  Eng.  av,  pounds,         molt,  by  2  2055  or   add  6-5. 

Prussian,  (including  Hanoverian,  Bruns- 
wick, and  Hessian,)  pounds,  to  Eng. 

avoir,  pounds,  "  "  1'031114  "     "  1-32. 

Fr.  livre,  (poids  de  marc)  to  Eng.  av.  Ibs.  "  "  1-079642  "     "2-25. 

Eng.  av.  Ib.  to  French  kilogram,  "  "  0'453414  "sb.  11-20. 

Eng.  av.  Ib.  to  French  livre,  "  "  Q'9262  "     "  1-13. 

Eng.  cwt.  (112  Ibs.)  to  a  metric  quintal, 

(=  100  kilog.  French,)  «  "  0'5078 

Eng.  cwt.  to  a  Prus.  centaer,  (=H01bs.)  "  "  0'9875  "     "  1-80. 

En<r-  cwt   to  a  quintal,  (old  measure= 

100  livres,)  "  "  1-0385  "  add  2-53. 

A  metric  quintal  to  an  English  cwt.  "  "  T971 

A  quintal,  old  meas.  to  an  Eng.  cwt.  "  "  0'963  "  sub.  1-27. 

A  Prussian  centner  to  an  Eng.  cwt.  "  "  1,0127  "  add  1-80. 

The  old  French  livre  contained  2  marcs,  or  16  ounces; 
a  marc  =  3778  Eng.  grs.  A  marc  at  Cologne,  (Ham- 
burgh, etc..)  =  8  oz.  =  3608  Eng.  grs. 

The  Russian  pood  (or  pud)  =  40  Russian  pounds  =  36 
English  pounds  avoirdupois. 

12  inches  English,  1  foot. 

3  feet,  1  yard. 

40  rods,  1  furlong. 

8  furlongs,  1  mile. 

3  miles,  1  league. 

6  feet,  1  fathom. 

60  geographical  miles,  1  degree. 

69£  statute  miles  (nearly,)  1  degree. 

A  French  meter=3  feet,  3-371  inches  English,  or  more 
correctly,  39-37079  inches  English=3  feet,  0  inches,  11-296 
lines  French. 

A  French  toise=6*3946  English  feet=6  old  French  feet. 

English.  French.  Prussian,  Danish  and  Rhenish. 

Foot:—         =     -9382928  =      -9711361. 

To  reduce  Approximately. 

French  feet  to  English.                 multiply  by    1-065765  or  add  1-15. 

English  feet  to  French,                       "         "  0-9382928  or  subt.  1-16. 

French  meters  to  English  feet,           "         "     3'280899  or  add  23-7. 

French  meters  to  English  yards,        "         "     1  093633  or  add  1-11. 

English  feet  to  French  meters,       ;  -*-       "  0-3047945  or  sobt.  7-10. 

The  French  foot  according  to  an  act  in  1812,  is  a  £  of  a 
33 


386  WEIGHTS,    MEASURES,    AND    COINS. 

meter,  but  this  measure  has  not  been  adopted,  the  old  Fiench 
foot,  (=  1*066  English  feet)  continuing  to  be  used. 

A.  German  geographical  mile=4  English  geographical 
miles,  or  about  4'633  Eng.  statute  miles  =  7407-40  meters, 

French  stere,  (cubic  measure)  =  35*34384  cubic  ft.  U.  S. 

French  litre  (liquid  and  dry  measure,)  =  61*07416  cubic 
inches,  or  1*05756  quarts  wine  measure. 

Value  of  different  weights,  in  English  avoirdupois  pounds, 

of  measures  in  English  feet  and  inches,  and  of  coins  in 

American  dollars. 

Amsterdam. —  1  centner  (lOOlbs.)  =  108*923  av.  Ibs. 

Batavia. — 1  picul  =  nearly  136  av.  Ibs. 

Bremen. —  1  centner  =  116  av.  Ibs.  ;  1  Ib.  =  1*1  av.  Ibs.; 
1  foot  —  llf  in  ;  1  rix  dollar,  (silver)  =  $0*787  ;  72  grotea 
=  1  rix  dollar. 

Calcutta. — 1  rupee,  (gold)  =$6.75  ;  1  rupee  (silver,)= 
$0.45,6  ;  1  candy  =  20  maunds,  =  500  Ibs.  av. 

Canton. — 1  picul  =  133£  av.  Ibs. ;  1  catty  =  1£  av.  Ibs. ; 
1  tael  =  l£  oz-  5  1  tael  =  #1*48  ;  10  mace  =  1  tael. 

Denmark. — 1  centner  (100  Ibs.)  =  110£  av.  Ibs.  ;  1  foot 
=12£  inches ;  1  rix  dollar,  (silver)  $0*52  ;  6  marcs  =  1 
rix  dollar  ;  16  skillings  =  1  rnarc. 

Florence  and  Leghorn. — 1  cantaro,  (100  Ibs.)  =  74*86 
av.  Ibs.  ;  1  palmo  =  9|  inches. 

France. — 1  franc  =  $0*186  ;  10  decimes  =  1  franc;  10 
centimes  =  1  decime. 

Genoa. — 1  peso  grosso  (100  Ibs.)  =  76f  av.  Ibs ;  1  peso 
sottile  =  69*89  av.  Ibs ;  1  palmo  =  9}  in. 

Great  Britain. — £l  =  20  shillings  sterling  =  $4*84  ;  1 
guinea  =  21  shillings  sterling  =  $5*08}. 

Hamburg. — 1  foot  =11*3  inches  ;  1  mile  =  .4*68  miles  ; 
1  marc  banco  =  $0*35 ;  current  marc  =  $0*28 ;  3  marca 
=  1  rix  dollar. 

Malta. — 1  foot,  10£  inches  ;  1  cantaro,  (100  Ibs.)  = 
174-5  av.  Ibs.  ;  1  pezza  =  $1. 

Manilla. — 1  arroba  =  26  av.  Ibs. ;  1  picul  =143  av.  Ibs. ; 
1  palmo  =  10*38  in. ;  8  rials  =  $1  ;  34  maravedis  =  1 
rial. 

Naples. — 1  cantaro  grosso  =  196*5  av.  Ibs.  ;  1  cantaro 
piccolo  =106  av.  Ibs. ;  1  palmo  =  lOf  in.  ;  1  ducat,  (sil- 
ver) =  $0*80  ;  10  carlini  =  1  ducat ;  10  grani=  1  carlino. 

Portugal— 100  Ibs.  =  101*19  av.  Ibs.  ;  1  arroba  =  22*26 


WEIGHTS,    MEASURES,    AND    COINS.  387 

av.  Ibs.  ;  1  quinta.  =  89'05  av.  Ibs.  ;  1  pe  or  foot,  =  12| 
in.  ;  1  mile  =  1*  mile  ;  1  milree,  or  crown  =  $1*12  = 
1000  rees ;  400  rees  =  1  cruzado. 

Prussia. — 100  Ibs.  =  103*11  av.  Ibs.;  1  quintal,  (110 
Ibs.)  =  113-42  av.  Ibs.  ;  1  foot=  1-03  feet ;  1  mile  =  4-68 
miles  ;  1  thaler,  $0'69  =  30  groschen  ;  12  pfennigs  =  1 
grosch. 

Rome. — 100  libras  =  74-77  av.  Ibs.  ;  1  foot  =  llf  in. ; 
1  canna  =  6£  fee*t ;  1  mile  =  7f  fur. 

Russia.— 100  Ibs.  =  90-26  av.  Ibs.  ;  1  pood,  (40  lbs.)= 
36  Ibs.  ;  1  Russian  pound  =  32  loths  =  96  zolotniks  ;  1 
verst,  (mile)  =  3500  Eng.  feet  =  5-3  fur. ;  1  inch  =  1 
English  inch  ;  1  foot  (in  general)  =  1  Eng.  foot ;  1  ruble, 
(silver)  ==  $0-78  =  100  copecks.  Bank  ruble  =  $0-223, 
or  nearly  22£  cents. 

Sicily. — 100  libras  =  70  av.  Ibs  ;  1  cantaro  grosso  = 
192*5  av.  Ibs. ;  1  cantaro  sottile  =  175  av.  Ibs.  ;  1  palmo  = 
9£  in.  ;  1  canna=  6£  feet ;  1  oncia,  (gold)  =  $2*40  =  30 
tari ;  20  grani  =  1  taro. 

Spain.— I  quintal  =  101-44  av.  Ibs.  ;  1  arroba  =  25*36 
av.  Ibs.;  1  fanega  =  1-6  bu.  ;  1  foot  =  11-128  in.;  1 
league  =  4'3  m.  nearly  ;  1  vara  =  2*78  feet ;  20  rials  = 
8l  ;  16  quintos  =  1  rial ;  2  maravedis  =  1  quinto. 

Sweden. — 100  Ibs.  (victualie)  =  73-76  av.  Ibs.  ;  1  foot 
=  11-69  in. ;  1  mile  =  6'64  m. ;  1  ell  =  1*95  feet. 

Smyrna. — 100  Ibs.  (1  quintal)  =  129*48  av.  Ibs. 
Trieste. — 100  Ibs.  =  123-6  av.  Ibs.  ;  1  foot  Austrian  = 
1*037  feet ;   1  mile  Austrian  =  4-6  miles  ;   1  florin,  (silver) 

;  $0-485  ;  60  kreutzers  =  1  florin. 
Venice.—  1  peso  grosso,  (100  Ibs.)  =  105-18  av.  Ibs.  ; 
1  peso  sottile  =  64*42  av.  Ibs.  ;   1  foot  =  M4  feet ;   1  li- 
ra =  1  franc  French  ==  $0-186  ;  100  centesimi  =  1  lira. 

A  troy  pound  of  fine  silver  is  worth  at  the  mint,  $15-51,515. 

A  troy  pound  of  standard  silver,  (American)  $13-86,615. 

A  troy  pound  of  fine  gold,  $248-27,586. 

A  troy  pound  of  standard  gold,  (American)  $223*25,581. 

1  dwt.  of  fine  gold,  $1*034. 

1  dwt.  of  American  native  gold,  usually,  $0*95  to  1*01. 

A  troy  pound  of  platinum  in  bars,  $90  to  $100. 

A  pound  av.  of  copper,  about  $0*21. 

A  pound  av.  of  tin,  about  $0-20. 
A  carat,  see  page  82. 


TABLES  FOR  THE  DETERMINATION  OF 
MINERALS. 

In  the  following  tables,  the  more  common  mineral  species 
(comprising  all  the  American)  are  arranged  in  subdivisions, 
to  afford  aid  in  ascertaining  the  names  of  species.  These 
tables  will  be  found  valuble  as  a  means  of  instruction  ;  the 
use  of  them  fixes  the  attention  on  distinctive  characters,  and 
thereby  impresses  the  peculiarities  of  species  on  the  mind. 

A  general  view  of  the  arrangement  in  Table  L  is  here 
annexed. 

I. — SOLUBLE  MINERALS, 

A.  No  effervescence  with  muriatic  acid. 

a.  No  deflagration  on  burning  coals. 

b.  Deflagration  on  burning  coals. 

B.  Effervesce  with  muriatic  acid. 

II. — INSOLUBLE  MINERALS. 

Luster  unmetallic, 

A.  Streak  uncolored. 

a.  No    odorous  or  colored   fumes   before   the 
blowpipe,  on  charcoal. 

1.  Wholly  soluble  in  one  or  more  of  the 

three  acids, 

*  Infusible.* 

f  Fusible  with  more  or  less  difficulty. 

2.  Soluble,  except  the  silica  which  separates 

as  a  jelly. 

*  Infusible. 

f  Fusible  with  more  or  less  difficulty. 

3.  Not  acted  on  by  acids,  or  partially  sol- 

uble without  forming  a  jelly. 

*  Infusible. 

f  Fusible  with  more  or  less  difficulty. 
fc.  Colored  or  odorous  fumes  before  the  blow- 
pipe, alone  or  on  charcoal. 

B.  Streak  colored. 

a.  No  fumes  before  the  blowpipe. 

*  By  infusible  is  meant,  not  capable  of  being  melted  alone  or  on  char- 
coal by  the  flame  of  the  common  blowpipe. 


TABLE    I.  FOR    DETERMINATION  OF    MINERALS.        389 

*  Fusible, 
f  Infusible. 

ft.  Fumes  before  the  blowpipe. 
II.  Luster  metallic. 

A.  Streak  unmetallic. 

*  No  fumes  before  the  blowpipe  on  charcoal, 
.j"  Fumes  before  the  blowpipe. 

B.  Streak  metallic. 

*  Malleable. 

•f  Not  malleable  ;  no  fumes  when  heated. 
J  Not  malleable  ;  fumes  when  heated. 
The  abbreviations  used  in  these  tables  are  as  follows  : 


Ad.           Adamantine. 

Limest. 

Limestone. 

Amyg.      Amygdaloidal. 

Mag. 

Magnetic. 

Antim.     Antimony. 

Mam. 

Mammillary. 

Arsen.      Arsenical. 

Mas. 

Massive. 

B,bh.       Blue,  bluish. 

Met. 

Metallic. 

Bl.           Blowpipe. 

Mur. 

Muriatic  acid. 

Bn,bnh.  Brown,  brownish. 

Nit. 

Nitric  acid. 

Bk,bkh.  Black,  blackish. 

Op. 

Opaque. 

Bor.          Borax.* 

Phos. 

Salt  of  phosphorus.* 

Bot.          Botryoidal. 

Fly. 

Pearly. 

Cleav.      Cleavable. 

Pros. 

Prisms. 

Char.        Charcoal. 

Prim. 

Primary  rocks.t 

Col.          Columnar. 

R,  rdh. 

Red,  reddish. 

Cryst.       Crystals,  crystalline. 

Rad. 

Radiated: 

Decrep.     Decrepitate. 

Ren. 

Reniform. 

Deliq.       Deliquescent. 
Dif.           Difficult,  difficultly. 

Res. 
Soda, 

Resinous. 
Carbonate  of  soda.* 

Div.          Divergent. 

Sol. 

Soluble. 

Efferv.      Effervescence. 

St. 

Streak. 

Exfol.       Exfoliate. 

Stalact. 

Stalactitic. 

Fib.          Fibrous. 

Stel. 

Stellate. 

Flex.         Flexible. 

Strl. 

Translucent  on  edges  only 

Fol.          Foliated. 

Strp. 

Semitransparent. 

Fus.          Fusible. 

Sulph. 

Sulphureous 

Gelat.       Gelatinize. 

Submet. 

Submetallic. 

Glob.        Globule. 

Sul. 

Sulphuric  acid. 

Gn,  gnh.  Green,  greenish. 

Trl. 

Translucent. 

Gran.        Granular. 

Trp. 

Transparent. 

Gy,  gyh.  Gray,  grayish. 

Vit. 

Vitreous 

Infus.        Infusible. 

Vol. 

Volatile. 

Insol.        Insoluble. 

Vole. 

Volcanic  rocks. 

Intum.      Intumesce. 

W,wh. 

White,  whitish. 

Lam.        Laminae. 

Yw,ywh.  Yellow,  yellowish. 

*  Blowpipe  flux. 

t  This  term  as  here  used  means  simply,  granite  and  the  allied  crys- 
talline rocks,  syenite,  gneiss,  mica  slate,  talcose  slate,  hornblende  rock, 
without  reference  to  age,  ^^* 


390        TABLE    I.  FOR    DETERMINATION    OF    MINERALS. 

The  Roman  numerals  refer  to  the  systems  of  crystalliza- 
tion, (page  32.) 

I.  Monometric.       IV.     Monoclinate. 

II.  Dimetric.  V.       Triclinate. 

III.  Trimetric.  VI.     Hexagonal  or  Rhombohedral. 
The  page  on  which  each  species  is  described  is  mentioned, 
that  the  student  may  conveniently  turn  to  the  fuller  descrip- 
tions for  a  farther  examination  of  a  mineral. 

The  kinds  of  rock  in  which  the  species  occur  is  often  addet* 
after  the  description. 

I.— SOLUBLE  MINERALS. 

A.    No  EFFEBVESCENCE  WITH  MURIATIC  ACID. 

a.  Not  deflagrating  on  burning  coals. 

Sal  ammoniac,  100.  I ;  crusts ;  G  1-5— 1-6 ;  wh,  ywh  ;  taste  acute  and  pungent ;  not 
deliquescent ;  Sul,  effervesce ;  mixed  in  powder  with 
quicklime  ammoniacal  odor ;  volatile. 

Alum,  127.  I ;  wh ;  very  soluble,  sweetish  astringent :  Bl,  fus !  intumescea. 

Common  salt,  104.  I ;  G  2-2—2-3 ;  w,  rdh,  gyh ;  saline ;  crystals  cubic :  Bl,  de- 
crepitates. 

Epsom  salt,         124.  Ill ;  G  1-7—1-8 ;  w ;  bitter  saline :  Bl,  deliq. 

White  vitriol,     252.  IU  ;  G  2—2-1 ;  wh ;  astringent-met :  Bl,  w  coating  on  charcoal. 

Borax,  107.  IV ;  G  1-7— 1-8  ;  wh ;  slow  efflor ;  sweetish  alkaline  :  Bl,  swells 

up  and  becomes  w  and  opaque. 

Glauber  salt,       102.  IV ;  G 1-4—1-5 ;  wh,  gyh ;  cooling  and  bitter :  Bl,  watery  fusion. 

Copperas,  227,  IV ;  G  2 ;  gn,  ywh,  wh  ;  astringent-met :  Bl,  red ;  Bar  gn  glass. 

Blue  vitriol,        280.  V;  G  2-2—2-3  ;  sky-blue  ;  nauseous  met:  Bl,  copper  reaction. 

White  arsenic,  305.  Capillary  cryst ;  bot,  mas ;  Gr  3-7 ;  w ;  taste  astringent,  sweet- 
ish :  Bl,  volatile,  alliaceous  fumes, 

b.  Deflagrate  on  burning  coals. 

Niter,  101.  Ill ;  G  1-9—2  ;  w,  not  deliquescent  or  efflorescent. 

Nit.  of  soda,      103.  VI ;  G  2—3 ;  wh ;  deliq ;  burns  with  a  deep  yellow  light 

Nitrate  of  lime,  123.  Cryst  efflorescences;  G  1-62;  w,  gy;  very  deliquescent:  Bl, 
watery  fusion,  scarcely  detonates. 

B.  EFFERVESCING  WITH  MURIATIC  ACID. 

Natron,  103.  IV;  G  1-4—1-5;  w,  gyh;  efflorescent. 

II.— INSOLUBLE    MINERALS. 

I.  LUSTER  UNMETALLIC. 

A.    STREAK  UNCOLOHED. 

a.    No  fumes  before  the  blowpipe  on  charcoal. 

1.    Wholly  soluble  in  one  or  more  of  the  acids,  (cold  or  hot),  usually  with  effervescence, 

*  Infusible. 
Hardness. 
Hydromagnesite,    125.  1-0—2-0  Whitish  crusts;    G  2-8;  adheres  to  the  tongue. 

Serpentine. 

Brucite,  126.  1-5—2-0  VI;  fol,  laminge  flexible ;  G  2-3—2-4 ;  w,  gnh ;  p'ly; 

trl;  no  effervescence.    Serpentine. 


TABLE    I.  FOR   DETERMINATION    OP   MINERALS.       391 

Hardness. 
Webstorite,  1'29.  1-5— 2-9  Ren,  mas ;  G  1-6—1-7  ;  dell ;  w,  op ;  adheres  to  th« 

tongues  nil,  sol,  n©  effervescence. 
Neinaiite,  125.  2  Siiky  fib ;  G  2-3—2-5  ;  gyh,  bh-w ;  fibres  separable, 

brittle  on  exposure.     Serpentine. 
Culc  spar,  US.  3;0— 2-0  VI ;  cleav !  fib,  mas  ;  G  2-3—2-5;  vtt,  p'ly,  w,  gy> 

bnh,  bk;  trp — op. ;  sometimes  soft  and  earthy; 
i  &l  intense  light. 

Arragontte  118.  3-5  IU  ;  mas,  fib  ;  G  2-8—3 ;  vit ;  w,  gyh,  bnh;  trp— 

op ;  effervesce  ;  Bl.  intense  light,  crumbles. 
Diallogite,  242.  3-5  VI;  cleav;   mas;  G  3-5—3-6;  Tit,  p'ly;  rdh;  til 

op ;  nit,  effervesces :  Bl,  bor,  violet  glass. 
Magnesite,  124.  3-0—4-6  VI ;  cleav  !  fib,  mas ;  G  2-9—3 ;  vit,  silky  ;  w,  ywh, 

bn  ;  trp,  op  ;  little  effervescence. 
Blende,  250.  3-5 — 4-0  I ;  dedec  cleav  ;  mas  ;   G  4 — 4-1 ;  resin-yw,  rdh, 

w  ;  trp,  strl ;  nit  sol,  emitting  suL  hydrogen :  Bl, 

bor  infus. 
Dolomite,  118.  3'5 — 4-0  VI;  cleav  1  mas;  G  2*8— 2-9 ,- vit,  p'ly ;  w,  gy,  bnf 

some  effervescence. 
Mesitine  spar,         229.  4-6  VI;  cleav  1  mas;  G  3-3— 3*65;   vit;  ywh,  bn   on 

exposure  ;  mur  slow  solution. 
Oligon  spar,  229.        "        VI ;  cleav ;  mas  ;  G  3-7—3-8  ;  vit ;  bn  on  exposure  : 

Bl,  bor  amethystine  glob. 
Yttrocerke,  206.  4-5—5-0  III ;  cleav;   mas;  violet  b,  gyh,  rdh-bn;  vit,  p'ly; 

strl,  op  ;  hot  mur,  sol ;  BL  whitens.     Prim. 

t  Fusible  with  more  or  less  difficulty. 

Witherite,  W9.  3-0— 3-5  IH;  mas,  fib;  G  4-2—4,4  w,  ywh,  gyh;  trl— op; 

wit  efferv :  Bl  fus !  op.  glob. 
White  lead  ore%      264.  3-0—3-5  HI ;  mas ;  G  6-1—6-5 ;  w,  gyh,  bnh  ;  ad,  res  ;  trp, 

trl ;  brittle ;  mur  eff :  Bl,  fus  !  on  char,  lead. 
Strontianke,  111   3-5  HI;  cleav;   fib,  mas;  G  3-6—3-7;   res,  vit;  gnh, 

ywh,  gyh;    effervescence  :  Bl,  fus  difl    colon 

name  reddish. 
Pyroraorphite,        266.  3-5—4-0  VI;  hexag  pms  ;  bot,  fib;  G  6-5—7-1 ;  bright  gn, 

yw,  bn ;  res  ;  strl,  strp  ;  brittle  ;  hot  wit  sol :  Bl, 

fus!     With  lead  ores. 

Spathic  iron,  228.     3—4-0  VI ,  cl,  mas  ;  G  37—3-9 ;  ply ;  ywh,  bnh,  gyh ;  dark- 

ens on  exposure ;  trl,  op  ;  pulverized,  some  eff : 

Bl,  fus  dif ! ;  blackens ;  iron  reaction. 
Wavellite,  130.        "       IU;  fib,  glob;  G  2-3—2-4;  p'ly,  vit;  w,  ywh,  bnh, 

gyh ;  trl ;  hot  nit,  sol,  vapors  corrode  glass :  Bl, 

fus,  intum,  colorless  glass. 
Cacoxene,  230.        «       Div,  rad,  fib,  silky ;  G  3-3— 3-4 ;  ywh-bn,  ywh ;  bn  on 

exposure :  Bl,  infus. 
Fluor  spar,  121.  4-0          I ;  cl !  mas ;  G  3-1—3-2 ;  vit ;  w,  yw,  b,  violet,  gn,  r, 

often  lively ;  trp,  trl ;  sul,  affords  fumes  that  cor- 

rode  glass  :  Bl,  fus,  decrep ;  phosphoresces  when 

heated. 
Apatite,  120.  4-5—5-0  VI;  hexag;  mas;  G  3—3-3;  vit,  res;   gn,  bh,  w 

rh,  bn ;  trp,  op ;  brittle ;  nit  sol  slowly  in  powd*" 


TABLE  I.  FOR   DETEianNATIOIf  OF  MINERALS 


Hardness.. 

witiiout  efferv  :  Bl,  fus  dif  I  bar  fas  r  Prim..  Gran. 

Himestone,  vole. 
Triplite,  241.  5>0          Lam,  mas  ;  G  3/4—3-8  ;  bkh-bs  ;  res,  ad  ;  nit  sol,  n« 

ef  :  M,  fus  !  bk  scsria;  bar  violet  glass. 
Troostite,  240.  5-&  VI  ;  mas  ;  G  4—4-1  ;  gnb,  y  w,  gy,  rdh-br  ;  v.it,  res  ; 

trj^  trl  ;  mur,  soi,  odorous  fumes  :  Bl,  fua  dif  E 

bor  violet  glass. 
Boraciter  !2&  7-0          I  j,  hemihed  cubes  ;  S  2-9—3  ;   w,  gyh  ;  fit,  ad  ;  strpF 

Crl  ;  pyro-electric  ;  mur,  sol  :  Bl,  fus.    Gypsum. 
2.  S(>iublgr  excepting  the  silica,  which  separate*  as  a  jelly. 

*  Infusible. 
Halloylite,  161.  1-0—2-0  Mas,  earthy  or  waxy  ;.  G  1-8—2-1  -,  w,  bh  ;  adhere* 

to  the  tongue  ;  »ul,  gelat  !  Bl,  infus. 
AUophane,  162.  3-0          Mas,  ren  ;  G  1-8—1-9  -r  vit,.  res  ;  bh,  guh,  y  wh,  trl  -r 

very  brittle  ;  gelat  !     Blr  intum. 

t  Fusible. 
Mesoler  167.  3*5          m  ;  fib  rad  ;  G  2-3—  2-4  ;  p'ly  ;  gyh-w,  ywh  ;  trl  :  JSft, 

fus  I    Amyg. 
Laumoniter  166v        •*        IV  ;  mas  ;  G  2-2—2-4  ;  vit,  p'ly  ;  w,  gyh  ;  trl  ;  w  and 

friable  oa  exposure  ;  gelat  I    Bl,  fus  w,  frothy, 

Amyg.  prim. 
Phillipsite,  168.  4-GK-4-5  III  -r  radrcrys$  often  crossed  ;  G  2—  2'2  ;  wrrdh  ;  vit  ; 

trp,  op  ;  mur  gelat  :  Bl,  fus,    Amyg. 
Tabular  spar,          141.  4-0—  5-0  V  ;  cl,  eubtib  ;  G  2-7—2-9  ;  p'ly,  vit  ;  w,  gyh  ;  trl  : 

mur  gelat  :  Bl,  fus  dif,  pearl  semiop.    Prim,  amyg, 
Thomaoniter  167.  4-5  —  5O  III  ;  cl,  lib,  rad  ;  G  2-3—2-4  ;  w,  bnh  ;  trp—  trl  ;  brittle  ? 

gelat  :  Bl,  fus  !  intum,  w,  op,    Amyg.  prim. 
Bysclasite,  142.  4-5—50  fib,  div  -t  G  2-2—2-4  ;  p'ly,  vit  ;  w,  bh  ;  trl,  strp  ;  very 

tough  under  the  hammer  ;  mur  gelat  y  Bl,  fue> 

op.    Amyg. 
Pectolite,  142.        "       fib,  div  ;  G  2-69  ;  vit,  p'ly  •,  w,  gyh  ;  after  heating 

gelat  in  mur  :  Bl,  fus  trp  glass.    Amyg. 
Electric  calamine,  253.        "        III  ;  cl  ;  mas,  bot,  nb  ;  G  3-2—3-5  ;  w,  b,  gn,  yw,  bn  ; 

trp  —  trl  ;  hot  nit  gelat  :  Bl,  fus  dif  !!  intuna  ;  phos- 

phoresces.    Stratified  rockf. 
FatroHte,  166.  4-5—5-5  III;  acic,  cryst;  div  fib  ;  G  2-1—2-3;  vit  ;  w,  ywh; 

trp,  trl  ;  gelat  !  Bl,  fus  1  op  glass.    Amyg.  vole. 
Analcime,  168.  5-0—5-5  I;  trapezohed;  mas;  G  2—  2-3;  vit;  w,  rhd,  gyh; 

trp—  op  ;    brittle  ;    mur  gelat  :   Bl  fus  !   intumv 

glassy  glob.     Amyg.  vole. 
Scolecite,  167.        "        HI  ;  div,  fib,  rad  ;  G  2-2—2-3  ;  vit,  p'ly  ;  w  ;  trp»  trl  ; 

nit  and  mur;  gelat  !  Bl  fus  !  op,  curls  up  in  outer 

flame.     Amyg.  vole. 
Datholite,  142.        «        IV  ;  glassy  crystals  ;  fib,  bot,  mas  ;  G  2—2-3  ;  w, 

gnh,  rdh  ;  trp,  trl  ;  nit  gelat  !  Bl,  fus  !  Amyg.  prim. 
Sodalite,  197.  5-5—6-0  I  ;  dodec  cryst  ;  mas  ;  G  2  2—  2-45  ;  vit  ;  gyh,  bn,  b  ; 

trp—  atrl  ;  nit  gelat  :  Bl,  fus,  colorless  glass. 
Nepheline,  180.  5-5—6-0  VI  ;  hexag  ;  coarse  massive,  subfib  ;  G  2-4—2-6;  vit 

greasy  ;  w,  ywh,  gnh,  bnh,  rdh  ;  trp  —  op  ;  gelat: 

Bl,  fus  dif;  blebby  glass.    Vole.  prim. 


TABLE    I.  FOR  DETEBTKINATIOTf    OP    MTNT5KAL8. 


3.     Nat  acted  «•  by  acid*,  or  partially  soluble  vitkout  forming  a  Jelly. 

t  Infusible. 
Hardness. 

U3.  1-0—1-5  VL;  foH  o>as ;  G  2-7— &8  ;  light  gn,  gnh-w,  gyn, 
p'ly,  unctuous;  laminae  flexible,  inelastic.    Prim. 
*       f  ol !  gran ;  apple-gm,  w,  bnh-gu,  ywh  ;  p'ly  ;  etra, 

strL:  Bl,  swells  op  !    Print. 

191.       -*        FolU   lain,  thin  elastic,  tough  ;G  2-8— -3;  colors 
various,  often  bright ;  p'ly  ;  tip,  strl;  EL,  fiiB  dif  1 


283.  2-0 — 3»0  mas,  bot ;  G  2 — 2-3  ;  bluish-gn ;  smooth  vit,  or  ear- 
thy ;  strl,  op ;   nit  sol,  except  silica . 

<Jibbsite,  131.  3"6— 3-5  Stalact,  crusts ;  G  2-3—2-4 ;  gyh-w,  gnh-w ;  dull. 

Oreenhyd.  nickel,  245.  3-0— 3-§  minute  globular,  crust;  G  3-05;  emerald-gn;  St 

paler;  vit;  trp,  trl ;  Bl,  loses  its  color. 
Blende,  250.  3-5-4«  I ;  dodec  cleav,  mas  ;  G  4—4-1 ;  resin-yw,  bn,  bh,  Wf 

rdh  ;  trp— op :  Bl,  bar  inf. 
968.  4-0—4-5  reniform  :  G  fi-3— 6  4  ;  ywh,  bah,  rdh;  resinous,  or 

like  gum  arabic  ;  til ;  Bl,  decrep ;  enam  on  char. 
148.  4-0— 5-0  IV;  fol !  lam  brittle ;  G  3—3-1 ;  rdh-bn  ;  met-ply  ; 

strl :  Bl,  ber  trp  pearl. 
129,  54  III ;  acic,  stel,  mas  ;  G  2-6—2-8 ;  vfc,  p'ly,  earthy ;  wt 

rh,  gyh ;  *wZ,  mostly  sol :  Bl,  decrep ;  soda  infus. 
296.  5-0          IV;  imbedded,  cryst,  clear  1  in  one  direction;  G 

4-8—5-1;  bn,  bnh-r;  vit,  res;  «trp,op;  brittle; 

mur,  decomposed.     Prim. 
175.  5-5— 6«  I :  trapezohedrons  ;  G  24—2-5  ;  w,  gyh ;  vit ;  strjfc 

trl :  Bl,  ber,  fus  dif.    Vole. 
292.       •"       II;  in  cryst;  G  3-8—3-9 ;  fine  bn,  1> ;  met-ad,  res ; 

strp,  trl :  Bl,  loses  eel ;  bor  fus  dif.     Prim. 

138.  6-i          Eeniform  ;  G  2-8—3 ;  b,  bh-gn  ;  waxy,  doll ;  trl. 

op  :  Bl*  dame  green  ;  ber,  fus. 

139,  5-5—6-5  Massive,  uncleav;  w,  yw,  r,  bn,  gn,  gy,  pale;  in 

eome  a  play  of  colors;  vit,  p'ly ;  trp,  Btrl;  Bl, 

decrep,  op. 
£73.  SO-ff-O  V  ;  in  prismsor  bladed  cryst ;  «  3-5— 3-7  ;  b,  w, 

bnh ;  p'ly,  vit ;  trp,  strl :  Bl,  bor  fus  dif,  trp.   Prim. 
147,  6-0—7-0  Mas,  subgran ;  G  2-9  -3-1 ;  leek-gn,  bh,  wh ;  vit ;  tri, 

strl :  Bl,  whitens ;  bor  clear  glass.    Prim. 
172.       •«       Col,  fib ;  G  3-2—3-6 ;  w,  gyh,  bnh ;  p'ly;  trl.  sfel; 

brittle.    Prim. 
295.        "        II ;  mas,  fib ;  G  6-5 7-1 ;  bn,  bk,  w,  gy,  r,  yw  ;  ad, 

res,  cryst  often  brilliant ;  strp,   op :  BL,  bor  on 

char  with  soda  affords  tin.    Prim. 

156,  6-5— 7-8  ffl;  imbeded  grains  or  masses  of  a  glassy  appear- 
ance ;  G  3-3—3-6 ;  ga,  bottle  glass  gn :  Bl,  darkens; 

bor  gn  glass ;  [rarely  fasible.j    Basalt,  etc. 
172.  6-5-5"5  V ;  col,  fib ;  G  3-0—34  ;  bn,  gyh ;  p^ly,  vit ;  trl,  strl; 

brittle:  Bl,  bor  infus.    Prim. 
174.        -        UI^  atoat prisms;  mas ;  G  2--9— 3-2  ;  vit,  p'ry ;  gy*. 


TABLE   I.  FOR    DETERMINATION    OF  MINERALS. 


Hardness. 

rdh  ;   tough  -T  structure  sometimes  tesselated*: 

Bl,  bor  fus  dif,  trp  glass.    Prim. 
Quartz,  132.  7-»          VI ;  mas ;   G  2-6—2-8 ;    colors  varies  •  vit ;   trp, 

op  :  Bl,  soda  fas  t  trp  glass,  elferv. 
Staurotide,  174.  7-0—7-5  III ;  stout  prisms ;  G  3-5—3-8 ;  bn,  rdh-ba,  bk ;  vit, 

res ;  strp,  op.     Prim. 
Zircony  200.  7-5  H ;  cryst,  seldom  mas  ;  G  4-4 — 4-8 ;  bo,  r,  y  w,  gy,  gn, 

w,  some  bright;   subad;  trp,  trl:  El?  bor,  clear 

glass.     Prim  ;  gran  li-mest. 
Topaz,  194.  7-5—8-0  III ;  prisms  with  basal  cleavage  !  mas,  col ;  G  3-4 — 

3-6  ;  pale  y  w,  gn,  b,  w  ;  vit ;  trl,  strl :  ££  bar  slowly 

trp  glass.    Prim. 
Spinef,  160i  8-0          I;  octahedrons,  etc  ;  G  3.5—4-6;  r,  bh,  gnh,  yh,  bnr 

bk ;  vit ;  trp,  strl,  (some  impure  crystals  soft)  : 

Bl,  bor  fus  dif.     Prim  ;  gran  limest,  etc. 
ChrysoberyV          199.  8'5  HI;  cryst;  G  3*5—3*;  bright  gn,  ywh,  gyb;  vit;: 

trp,  trl :  Bl,  bor  fus  dif!     Prim. 
Sapphire,.  158.  9-01          VI ;  mas  ;  in  grains ;  G  3"-9— 4^2 ;  b,  r,  yw,  bn,  gyh-b, 

gy,  w ;  vit ;  trp,  trl :  Bl,.  bor  fua  dif.  Prim ;  gran 

limest. 

Diamond,  8(X  1ft©!        I ;  G  3-4—3*7 ;  w,  b,  r,  yw,  gn,  bn,  gy,  bk ;  adaman- 

tine ;  trp ;  strl. 

f  Fusible  with  more  or  less  difficulty. 
Tale,  143.  1-0—1-5  III;  fol!  mas;  G  27—2-9;  light  ga;  gnh-w,  gyh; 

p'ly,  unctuous ;  laminae-  flexible,  not  elastic :  Blf 

infus,  or  fas  dif!!     Trim ;  gran  limest. 
Chlorite*  145.  1-5          Fol ;  mas  gran ;  G  2-6—2-9  ;  olive  green ;  p'ly ;  sul 

decomp  :Bl.  fus  dif !  sometimes  to  a  black  glassy 

bead.  Prim. 
Gypsum*  112.  1-5—2-0:  IV  ;  fol !  gran,  stel  r  G  2-2—2-4 ;  w,  gyh,bnb,  rh.bk 7 

trp, trl;  lam  flexible,  inelastic  :  Bl,  fus  dif;  whi- 
tens, exf,  and  becomes  friable ;  Strat.  prim.  void. 
lfic%  191.  2-Q-— 2-5  Pel  fJ  lam  thia  elastic,   tough  ;   G  2-8—3 ;   colors 

various,  often  bright ;  p'ly ;  trl,  strl:  .K, fus  dif !> 

Prim,  etc. 
Cryolite,  132.        "        Mas,  fol ;  G  2-9—3 ;  w ;  vit,  p'ly  ;  fasible  ia  a  candle. 

Prim. 
Serpentine  145.  2-0—3-5  III ;  mas  ;  sometimes  thin  fol,  fsl  brittle ;  fib ;  G 

2-4 — 2-6 ;  dark  or  lighfe  gn,  gah^wr  bh-w  -t  trl — op  ? 

feel  often,  greasy  :  Bl,  fus  dif!! 
Ghlorophyllite,      1(52.  .2-0--4-0,  VI ;  fol  prisms ;  fol  brittk) ;  G.  2:7^-2-8 ;  dull  green, 

gyh,  bnh  ;  p'ly,  vit :  HI,  fus  dif!!    Prim  -anih  iolite* 
Anglesite,  264.  2-5— 3-ft  III ;  mas ;  laaa  ;  Gr  6  2— 6-3 ;  w,  ywh,  gyh ;  gnh ; 

ad,  vit,  res ;  trp,  tri  :  Bl;  fus  »   decrep  ;  fan  char, 

load  globule. 
Ashydrite,  M4v  2-5>— 3-&  III ;  rectang  cleav  !  mas ;  G  2-8—4};  w,  rh,  feK  gj^i 

prly,  vit:  Bl,  fus  dif  r  whitens ;  not  exl 


*•  Thia  tesselated  variety  b  often  quite  soft,  owing  to  impurities^ 


TABLE    I.  FOR    DETERMINATION    OP    MINERALS.        895 

Hardness. 

Cukstinc,  110.  3-0—3-5  III ;  mas,  fib,  lam  ;  G  3-8 — 4  ;  w,  bh,  rh ;  vtt,  res; 

trp,  strl  :  Bl,  fus,  decrep  ;  phosphoresces. 

Heavy  gp,,r,  1€6.  "  ffi  ;  mas,  fib,  lam .  G  4-3—4-8 ;  w,  gyh,  ywh,  bn; 

vit,  p'ly,  res ;  trp,  strl :  Bl,  fus,  decrep.  Strat} 
prim. 

Heulaadite,  164.  3-5—4-0  IV ;  fol  i  fol  brittle ;  G  2-2 ;  w,  rdh,  gy,  bnh ;  ply, 

vit;  trp,  strl;  *tids  sol,  except  silica:  Bl,  fua, 
intern,  phosphorescent  Amyg,  prim. 

Stilbite,  165  35— 4O  HI ;  fol !  rad,  div  ;  G  2-1—2-2 ;  w,  ywh,  rh,  bn ;  p'ly ; 

trl,  strp;  nit,  silica  deposited:  Bl,  fits  I  intum, 
colorless  glass.  Amyg,  prim,  &c. 

SchiUer  spar,  148.  «  Mas,  fol ;  fol  brittle ;  G  2-5—2-7.;  dark  gn,  or  sub- 
met  :  Bl,  fus  dif  n  gives  off  water. 

Chabaztte,*  1€9.  4O — 4-5  VI ;  in  rbdns.  nearly  cubes,  and  complex  small 

crystals  ;  G  2—2-2  ;  w,  rdh,  ywh ;  vit;  strp,  trl; 
mur,  silica  deposited:  Bl,  fus  I  blebby  enameL 
Amyg,  velc,  prim. 

Harmotome,  168.  «  IH  ;  crystals  often  crossed  ;  G  2-3— 2-5;  w,  rdh; 

vit ;  strp,  op ;  mur,  silica  deposited :  Bl,  fus,  clear 
w  glass ;  phosphoresce*.  Amyg,  prim,  etc, 

Tungstateof  lime,  300.  "  II ;  mas  ;  G  6-^6-1 ;  vit,  rea  ;  ywh,  w ;  strp— op ; 
it  it.  becomes  y  w,  but  is  not  dissolved :  Bl,  fas 
dif!!  decrepitates.  Prim. 

Apophyllite,  165.  4-5--50  II;  glassy  cryst;  transverse  cleav;  G  23—2-4;  w; 

gab,  ywh,  rdh ;  p'ly,  vit ;  trp,  op ;  nit,  sol,  but 
hardly  gelat :  Bl,  fus,  exfoliates.  Amyg. 

Monazfte,  306.  5-0  IV ;  imbedded  cryet,  one  cleavage  1  G  4-8—5-1 ;  bn, 

bnh-r ;  vit,  res  ;  strp,  op ;  brittle ;  mur,  decom- 
posed :  Bl,  fus  dif !!  Prim. 

Pyrochlore,  208.  50  IV;  imbedded  oct  cryst;  G  3-8 — 43;  yw,  ywh; 

res,  vit ;  St  slightly  colored ;  trl :  Bl,  fus  dif  !l 

Sphene,  292.  5-0  IV ;  usually  in  acute,  thin  crystals ;  G  3.2—3-5  ;  bn, 

yw,  gy,  bk;  res,  ad;  strl,  op:  Bl,  fus  dif!  tor 
yw  glass.  Prim,  gran  limestone,  etc. 

Scapolite,  180.  5O— €O  II;  mas;  sabcol ;  G  2-6—2-8  ;  w,  gyh,  rh;  vit,  p'ly; 

trp — op  :  Bl,  fus.  Prim,  gram  limestone. 

Hornblende^  152.  «  IV ;  fib,  rad ;  mas  ;  (some  var  fib  like  flax  ^  G  2-9 — 
3-4  ;  gn  to  bk  and  w ;  vit,  p'ly ;  trp,  op  :  Bl,  fus, 
or  dif !  fus.  Prim,  trap,  trachyte,  etc. 

Pyroxene,!  150.  "  IV;  fib  ;  mns ;  cleav ;  G  3-1 — 3-5 ;  gn  to  bk  and  w,- 

vit,  p'ly  ;  trp — op  :  Bl,  fus ;  glassy  globule.  Prim, 
basalt,  mlc,  etc. 

Lazulite,  131.  5-5— €-0  IV ;  mas ;  G  3—3-1 ;  pure  b,  gnh-b ;  vit ;  strp— op : 

Bl,  fus,  bar  clear  glob. 


*  The  var.  Gmelinite  gelatinizes  in  acids. 

t  Some  fibrous  varieties  (asbestus)  of  hornblende  and  pyroxene  are  quite  soft, 
and  resemble  those  of  serpentine  •  and  others  are  like  flax,  or  have  nearly  the 
texture  of  felt. 


396     TABLE  r.  FOR  DETERjriNATicra  OF 


Hardness 
Lapia  Lazuli,          I96r  5-5—60 

Feldspar,  176.  6-0 


Yfl:  6-8 


Labradorite,  178.  6-9 

Chondrodite,  157.  5-5  —  6-5 

Obsidian,  341.  5-5  —  6-5 

Manganese  spar,  239.  5-5—7-0 

Petalife,  182.  6-0—  G-5 

Idocrase,  184.  6-5 

frehnife,  170.  6-0—6-5 

Epidote,  182.  6-0  —  7-0 

Spodumene,  181.  ff-5—  7-0 

Axinite,  190:        «• 


Garnet^  184.  6-5—7^  I  ;  cryst,  mas,  gran  ;  G  3-5  —  4-3  ;  r,  bn,  w,  gn,  bk, 

often  bright  ;  vit,  res  ;  trp,  trl  :  Bl,  fas,  no  efferv, 

bk  glob.    Prim,  etc. 
Boracite,  126.  7-0  I  ;  hemihed  cubes  ;  G  2-9—3  ;  w,  gyh  ;  vit,  ad  ;  strp, 

trl  ;  pyro-electric  :  Bl,  fus,  intum.     Gypsum. 
lolite,        .  190.  7-0          HI  ;  mas,  glassy  ;  G  2-6—  2-g;  b,  gyh-b,  bnh  ;  trp, 

trl  :  Bl,  fus  dif  f  bor  trp,  glass.      Prim. 
Tourmaline,  187.  7-0—8-0  VI  ;  col,  mas  ;  G  3—3-1  ;  bk,  bn,  gn,  r,  b,  w,  often 

bright  ;  vit,  res  ;  trp,  op  ;  pyro-electric  :  Bl,  fus, 

intum.    Prim,  etc. 
Euclase,  399.  7-5  IV  ;  in  crystals,  cleav  ;  G  2-9—3-1  ;  pale-gn,  b,  w  ; 

vit,  brilliant  ;  trp,  strl  :  Bl,  fus  dif  I  intum.  Prim. 
Beryl,  197.  7-5—8-0  VI  ;  hexag  pms,  mas  ;  G  2-6—  2'8  ;  gn,  bright  or 

dull.bh,  ywh  ;  trp,  strl:  Bl,  fus  dif  ;  bortrp  glass. 


I  ;  dedec  ;  mas  ;  G  2-5—2-&  ;  rich  b  ;  vit;  trl—  op  , 

Bl,  fus,-  trl  or  op  glass. 

IV  ;  cleav,  mas  ;  6  2-3—2-5;  wh,  gyh,  rh,  bh,  gnh  ; 
p'ly,  vit;  trp,  strl  ;  mur,  so  action:  Bl,  fas  dif;'. 
bar  tip  glass. 

V  ;  cleav,  mas  ;  G  2-6—2-7  ;  w,  gyh,  gahrrtirbh  ;  p'ly,, 
Vit;  trp,-strl;  mur,  no  action:  Bl,  fus  dif;  flame 
yellow;  may  generally  be  distinguished  from 
feldspar  by  its  purer  whife  color. 

V  ;  clear,  mas  ;  6  2-6—2-3  ;  chatoyant,  gy,  gnh,  bn;. 
Fdh-bn  :  p'ly,  vit;  strl;  hot  mur  decomp  :  Blr 
fus  easily,  colorless  glass.  Prim. 

IV  ;  gran  mas  ;  G  3-1—  3-2  ;  ywh,  bnh-yw,  rh,  gnh  -r 
vit,  res  ;  trp,  strl  ;  brittle  :  SI,  fus  dif!!  bor  fus  r 
ywh-gn.     Gran  limestone. 

Mas,  like  glass  ;  G  2-2—28  ;  bk,  gy,  gn  ;  vit,  p'ly  ;. 
Bl.fue. 

V  ;  mas  :  G  3-4—3-7  ;  fleeh-r,  dark  bn  on  exposure  ; 
vit  ;  trp,  strl  :  Bl,  fus  bkh  glass  ;  bor  violet.  Prim, 

Cleav  mas,  gran  ;  G  2-4—  2'5  ;  w,  bh,  rh,  gnh  ;  vit^ 
p'ly  ;  trl  ;  phosphoresces  .  SI,  fas  ;  &or  trp  glass, 
Prim. 

II  ;  mas  ;  G  3-3—3-4  ;  bn,  gn,  w  ;  vit,  resr  cryst  often 
brllliaHt  ;  trp,  strl  :  SI,  fus  !  trl  glab.   Prim  ;  vole  ? 
gran  limest. 

III;  bot,mas;  G  28—3;  light  gn,  W;  vit,  ply;  trlr 
strl  ;  tough  ;  mur  sol,  exc't  silica  :  Bl,  fas.  Amyg, 
prim. 

IV  ;  mas,  gran,  col  ;  G  3-3  —  3'5  ;  ywh-gn,  gy,  bn,  bhr 
rh  ;  vit,  p'ly  ;  trp,  op  :  Bl,  fus.    Prim,  etc. 

Cleav  mas,  gran  ;  6  3-1—5-2;  gyh-w,  gnh  ;  ply  :  Blr 
fas,  intam,  exf,  colorless  glass.  Prim. 

V  ;  cryst  ac^te-edged  ;  Gr  3-2—3-3  ;  deep  bn  ;  vit, 
brilliant  ;  trp,  strl  :  Bl,  fns  !  intum  dark  gn  glass  ; 


Prim. 


TABLE    I.    FOR    DETERMINATION    OF    MINERALS.        397 


b.    Colored  or  odorous  fames  before  the  blowpipe  OB  charcoal. 

Hardness. 
Horn  silver,  323.  1-0— 1-5  I ;  mas,  like  wax  ;  G  5-5—56 ;  gy,  bh,  gnh ;  trl,  strl ; 

scctile  ;    fus.  ifl  caadle,  yielding  odorous  fumes. 

Silver  ores. 
Mimeteme,  267.  2-7—3-5  VI;  mas;  G  64— 6-5;  pale  yw,  bnh,  bnh-r;  strp, 

trl;    hot  nit  sol;  BL  fus  11  on  char  alliaceous 

fumes.— Lead  ores. 
Scorodfte,  230.  35- 4-9  III ;  mas  ;  G  31—3-3 ;  leek-gn,  gnh  w,  bh,  bnh ;  ad, 

vit ;  strp,  strl ;  Bl  fus  i  alliaceous  fumes. 
Blende,  238.        «        I ;  dedec  cleav !   mas ;  G  4—4-1 ;  resin-y  w,  rdh, 

wk ;  trp,  strl ;  nit  sol,  emitting  sulph  hydrogen 

Bl.  on  char  at  a  high  heat  fumes  of  zinc. 
Bismuth  blende,     258.  3-5—4-5  I;  mas,  col;  G  5-9—6-1;  bn,  gyh,  ywh;  res,  ad 

Bl,  fus,  w  fumes.     Prim. 
Calamme,  253.  5-0  VI ;  mas,  rea,  bot ;  G  4-2—4-5  ;  gyh-w,  gnh,  bnh ; 

vit,  p'ly ;  strp,  trl ;  nit  efferv :  Bl,  infus ;  OB  cftcr, 

w  fumes.    Usually  with  lead  «r«. 

B.    STKEAK  COLORED. 

a.    No  fumes  be/ere  the  blovpipe. 

*  Fusible. 

Minium,  263.  soft        Mas,  pulv ;  G  4-6 ;  bright  red :  Bl,  fus ;  on  char, 

glob  lead.    Lead  ores. 
Vivianite,  229.  1-5— 2K)  IV;    fol!    lam.  flex;    mas;  G    2-6— 27  ;  bkh-gn, 

dark  b  ;  St,  bh-w,  b ;  nit  or  ml  sol :  Bl,  fus  1 1 

decrep,  dark  bn  scoria,  magnetic. 
Uranite,  210.  20—2-5  II ;  fol !  mas ;  G  3—3-6  ;  bright  gn,  yw  ;  St,  paler; 

p'ly,  ad ;  trp,  strp ;  nit  sol,  no  efferv :  Bl,  fus, 

bk  glob.    Prim. 
Cup.  anglesite,       264.  2-5—3-0  IV  ;  cleav !  G  53—5-5 ;  fine  azure  blue ;  St,  paler; 

ad,  vit;  trl,  strl:    Bl,  reaction  of  copper  and 

lead.    Lead  ores, 
Chromate  of  lead,  267.  25— 3-0  IV;  mas,  col;  G6;  bright  r;  St  orange  ;  ad;  trl; 

sectile ;  nit  sol,  no  efferv  :  Bl,  blackens,  decrep, 

shining  slag.    Lead  ores. 
Green  malachite,    261   35 — 4O  IV;   mam,  bot,  crust;  G  4 — 4-1;  gn ;   St,  paler; 

vit,  silky,  earthy ;  trl,  op ;  nit  sol,  efferv :  Bl,  fua  I 

bk :  bor  gn.     Copper  ores. 
Red  copper  ore,    279.        *       I ;  mas,  fib ;  G  5-9—6  ;  deep  red ;  St,  bnh-r ;    ad 

submet ;   strp,  strl ;  nit  sol,  efferv :   Bl  fus !  on 

char  metallic  copper.    Copper  ores. 
Pyromorphite,       266.        "        VI ;  mas ;  G  68—7-1 ;  gn,  bn,  gy ;  St  yw ;  res  ; 

strp,  etrl ;  hot  nit  sol,  no  efferv :  Bl  fus  I    Le*d 

ores. 
Azurite  283.        "        IV ;  mas,  earthy ;  G  3-5—3-9 ;  azure  b,  dark  b ; 

St  paler;  vit,  ad;  trp,  strl;  nit  efferv:  Bl,  fus! 

copper  r  ^action     Copper  ores. 

34 


TABLE    I.    FOR    DETERMINATION    OF   MINERALS. 


Hardness. 
Fyrochlore,  298.  5-&          1 ;  octahed  cryst;  G  42— 4-3;  rdh-bn,  yw,  y,i-jj 

St  paler;  res^vit-,.  strl,  op:  El  ywh-bn,  fus  cHfJ 

bar  y  w  glob  in  outer  flame.     J'rim. 
Triplite,  241.  5'0— 55  M:ig,  cleav;  G  3-4—3-8;  bkh-bu  ;  St  ywh-gy ;  :  esf 

ad ;  strp,  op  ;  nit  solr  no  efllrv  :  SI  fus  !  bk  £c»- 

ria;  bar,  violet 
Monazite,  206.        »       IV ;  cryst ;  G  4-8—5-1 ;  bnr  rdh-bn,  gyh ;  St  rdh-vrr 

bnh-w;  vit,  res;  strp,  op;  Bl  fus  dif!  I  yw,  op. 

Prim, 
Chondrodite,          157.  6-0— fl'5  IV  ;  gran  mas ;  G  3-1—33 ;  light  y  w,  bn,  rdh ;  St 

paler;   res,  vit;  trp,  strl;  very  brittle:  Bl  fiis 

dif!!  loses  color.     Gran  limest.    Prim. 
Allanite,  207.        "        V;  acic  cryst;  mas;    G  3-2 — 4-1;    bnh-bk,   gnh; 

swbmet,  res ;  St  gnh-gy  ?  op,  strl :  Bl  fus,  froths, 

bfe  scoria.     Prim. 

f  Infusible. 

Wad,  241.  1-0          Mas,  often-  earthy  ?  G  3  7  ;  bn,  bk.  soils :  Bl,  man- 

ganese reaction. 

Black  copper,         279.        "        Mas,  or  earthy  ;  bk,  bnh-bk ;  St  bk  ;  soils  :  Bl,  cop- 
per reaction.     Copper  ores. 

Earthy  cobalt,        248.        "        Earthy,  mas ;  bk  :  Bl,  bor,  blue  from  cobalt. 
Cacoxene,  230.  30 — 4-0  Fib,  rad  ;  G  3.3—3-4  ;  ywh-bn,  y  w ;  St  ywh ;  silky  : 

Bl,  bor  dark  red  bead.    Iron  ores. 

Blende,  250.        *        I ;  dodec  cleav  ;  mas  ;  fib  ;  G  4 — 4-1 ;    resin  y  w, 

bn,  bk,  red ;  St  pale  ;  strp,  op  ;  nit  sol,  emitting 

sulph  hydrogen :  Bl,  bar  infus ;  on  char,  at  high 

heat,  fumes  of  zinc. 

Warwickite,  293,  3-0—4-0  Prismatic  cryst ;  G  3— 3-3  ;  bah,  tarnished  bhr  or 

wh  ;  St.  bnh ;  met-p'ly ;  res.    Gran  limest. 

Red  zinc  ore.         251.  4-0  III;  fol !  mas;  G  5-4 — 5-6;  bright  r;  St.  orange; 

subad  ;  strl,  op ;  nit  sol,  no  efferv :  Bl,  bor  y  w 
glass ;  soda  a  zinc  slag. 

VI;  cryst;  G  3-2—3-3;  emerald-gn;  Bt  gn ;  vit, 
res;  trp,  trl ;  ntur,  sol,  no  efferv:  Bl,  decrep, 
y  wh-gn  flame  ;  copper  ores. 

Mas,  mam,  etalact,  bot ;  earthy  ;  G  3-9 — 4-1 ;  dull 
bn,  bk,  ywh  ;  res,  submet ;  Btrp,  op :  Bl,  bk,  mag- 
netic, iron  reaction. 

222.  5-5  I ;  mas,  uncleav;  G  4-3 — 4-5 ;  iron  bk,  St  bn  ;  nearly 

dull,  submet ;  op :  Bl,  bor  fine  gn  glob.  Serpentine. 
209.  5.5  Mas,  bot ;  G  6-47  ;  bnh-bk,  velvet  bk  ;  St  bk ;  sub- 

metallic  or  dull ;  nit  slow  sol  i  Bl,  bor  a  gray 
scoria.    Prim. 

240.  50—6-0  Mas,  bot ;  G  4—4-4  ;  bk,  dark  steel  gy  ;  St  bkh; 
submet ;  op  ;  mur  sol,  odorous  fumes  :  Bl,  man- 
ganese reaction. 

291.  b-0— 6-5  II ;  rarely  mas  ;  G  4-2—4-3  ;  rdh-bn,  ywh,  gy;  St 
paler ;  ad,  mct-ad  ;  trl,  op :  Bl,  bor  y wh-r  glass  ; 
crystals  often  aciculan  Prim,  etc. 


Dioptase,  284.  5-0 

Brown  hematite,  220.  5-0—5-5 

Chromic  iron, 
Pitchblende, 

Psilomelane, 
Ruffle, 


TABLE    I.  FOR    DETERMINATION    OF   MINERALS.        399 

Hardness. 

Tin  ore,  293.  6  0— 7tf  II ;  mas,  fib  ;  G  65—7-1 ;  bn,  bk,  y  w,  r;  St  paler;  ad ; 

strp,  op :  Bl,  on  char,  with  eada,  tin  glob.    Print. 

b.  Fumes  bcfsre  tie  blowpipe. 

Red  antimoay,  303.  1-0—1-5  IV,-  capil  tufts  and  div  ;  G  4-4 — 4-6;  cherry-r;  St 
bnh-r;  ad,  met;  Btrl;  nit  w  coating:  .K,  fusil 
or  char,  volat  Prim. 

Cobalt-bloom,  248.  1-5—2-0  IV;  foil  fib,  stel,  earthy;  29—3;  crimson  and 
peach-blossom  r,  gyh,  gnh  ;  St  paler  ;  dry  pow- 
der lavender  b ;  lain  flex.-  Bl,  fus  !  on  char  allia- 
ceous, her  fine  blue  glob.  Prim,  cobalt  ores. 

Orjriment,  305.        "        in ,•  foil  lam  flex;  mas;  G  3-4— 3-5;  lemon  yw; 

St  paler  ;  p'ly,  res  ;  strp,  strl ;  eectile  :  Bl,  sul- 
phur and  arsenical  fumes.  (Realgar,  p.  305,  dif- 
fers IK  its  red  cok>r  and  orange  streak.) 

Copper  mica,         264.  2-0  VI ;  fol !  mas  ;  G  2-55 ;  emerald  gn,  grass  gn  ;   St 

paler ;  jp'ly,  vit ;  trp,  trl ;  sectile  :  Bl,  alliaceous 
femes,  rdh-bn  scoria. 

Sulphur  S6.  1-5—2-5  UI ;  mas ;  G  2-07  ;  y  w  ;  rdh,  gnh  ;  res  ;  trp,  strl ; 

burns,  b  flame. 

Red  suVer,  323.  2-0—2-5  VI;  mas;  G  5-4^5-9,  light  r,  to  bk ;  St  r ;  ad,  met ; 

strp,  op :  Bl,  fus !  1  sulph  and  arsen  fumes ;  silver 
•res. 

Cinnabar,  270.        "        VI ;  cleav ;  mas ;  G  8— 80. ;  bright  r,  bnh-r,  bn ;  st 

r,  bnh ;  ad,  sub-met ;  strp,  op  ;  nit,  sol,  r  fumes : 
Bl,  wholly  voL  Strat.  prim. 

285.  2:5—3*)  ffl;  clear;  mas;  G  4  -4— 4-5;  bright  gn,  olive-gn; 
Stgnh;  ad,  vit;  strl:  -B^fus!  mariaiic  fumes; 
copper  reaction  ;  copper  ores. 


H.  LUSTER  METALLIC. 

A.  STREAK  UNMETAM.IC. 
*  No  fumes  before  the  blowpipe  on  charcoal. 

Wad,  241.  1*          Mas,  often  earthy;  G  3-7 ;  ba,  bh ;  soils ;  submet: 

Bl,  manganese  reaction. 
Earthy  cobalt,        248.        "        Mas,  earthy,  hot ;  G  2  2—2-3  ;  bh-bk,  bnh-bk ;  St  bh 

bk  ;  sectile :  Bl,  arsen  fames ;  bar  blue  glass. 
Pyrolusfte,  240.  2<0— 2-5  III ;  col,  rad ;  mas  ;   G  4-8 — 5  ;    iron-bk,  St   Kk ; 

mur,  odor  of  chlorine:  Bl,  infus ;  tor  amethyst, 

glob. 
Cinnabar,  £70.        «        VI;  cleav  ;  mas:  G  8- «•!;  r,  bnh-r,  gyh,  dark  bn; 

St  r ;  strp,  op ;  nit  sol,  r  fumes :   Bl,  volatile. 

Strat,  prim. 
Wende,  250.  3-5—4-0  I ;  dodec  cl !  mas  ;  G  4—4-1 ;  bn,  bk ;  St  yw,  bnh; 

op  ;  submet,  bright :  Bl,  fus.    Prim,  ttrat,  etc. 
Manganite,  242.  4-0—4-5  HI ;  mas  ;  G  4-3 — 4-4  ;  dark  steel-gy,  iron-bk ;  St 

rdh-bn,  bkh;  Bl,  infos;  bar,  amethystine  gleb. 


400       TABLE    I.   FOR    DETRRMIXATIOW   OF  MINERALS 


Hardness. 

Brown  hematite,.  220  5-0—55  inam,  bat,,  stalact,  mas ;  G3f9— 4 ;  ba,  bkh ;  St  ywf> 
bn ;  strp,  op  ;  BO  action  on  magnet :  Bl,  infus, 
bk  and  magnetic. 

Wolfram,  225.  5-0— 5-5  III ;  mas  ;  col,  lam  ;  G  7-1—7-4  ;  gyh-bk,  bnh-bk  ,- 

St  dark  rdh-bu ;  submet :  Bl  fua  ^  decrep,  bar 
gn  bead.  Prim. 

Chromic  iron-,  222.  "  I ;  mas ;  G  4-3 — 4-5  ;  iron  bk,  rather  dull,  brittle  ; 
St  bn ;  often  slightly  magnetic :  Bl,  infus  ;  bov 
fine  gn,  fus  dif.  Serpentine. 

Pitchblende,  209.  5-5  Mas,  boi;  G  6-4-7;  bnh-bk,  yelvet-bk ;  St,bk;  sub- 

met  ;  nit  slow  sol :  Bl,  bor  gray  scoria.  Prim. 

PBilomelane,  240.  5-0— 6-ft  Mas,  bot ;  G  4 — 4-4  ;  bh,  gyh  to  dark  steel  gy ;  St 

bnh-bk,,  shining;  brittle:  Bl,  iixfus,  bar  violet. 
Manganese  ores. 

Columbite,  224.  "  III ;  mas  ;  G  5-9—6-1 ;  bnh-bk,  bk,  oftea  with  a 

steel  bltae  tarnish  ;  St  dark  rdh-bnr bnh-bk;  sub- 
met:  Bl.  infus,  bor  fus  dif.  Prim. 

Yenite,  226.  5-5— 6-0  III ;  mas,  col ;  G  3-8—41 ;  iron  bk,  bnh ;  St  gnh, 

bnh;  submet;  britfle :  Bl,  fus;  bor  bk  mag 
glob.  Prim. 

Specular  ironj  218.  5<-5— 6-5  VI ;  mas  ;  G  4-5 — 5-3 ;  iron-bk  and  cryst  brilliant  - 
Sfi  r,  rdh-bn  :  Bl  infus,  bor  iron  reaction,  glob 
finally  mag.  Prim,  strat,  vote. 

Magnetic  iron,  216.  "  I ;  mas  ;  G  5 — 5'1 ;  iron-bk  ;  St  bk ;  strongly  magy 
netic  :  Bl,  infus,  boy  iron  reaction.  Prim,  strat. 

Franklinite,  221.  «  I;  mas;  G  4-8— 5-1;  iroa-bk;  St  dark  rdh  bn; 

slightly  magnetic  :  Bl,  infus  ;  at  high  heat  zinc 
fumes.  Prim. 

Arkansite,  200.  7—7-5-  III ;  G  3-85-;  iron  bk;  St  dark  ash  greem 

t  Fames  before  the  blowpipe. 

Bark  red  flflver,     323.  2-5          VI;  mas;  G  5-7—5-9;  iron-bk,  lead-gy;  St  red; 

met-ad :  Bl,  fus !  !  b  flame,  sulph  aad  antimony 

fumes.     Silver  ores. 

Variegat'd  copper,  277.  3-0  I;  mas;  G5 — 5-1;  pinchbeck-bn,  copper-r,  bh  tar- 
nish ;  St  pale  gyh-bk ;  brittle :  Bl,  fus  ;  on  char 

sulph  odor,  glob  mag.    Prim,  strat,  with  coppev 

ores. 
Copper  pyrites,      275.  3-5 — 4-0  II ;  mas  ;  G  4 — 4-2;  brass  yw ;  St  gnh-bk  ;  brittle . 

nit  sol,  gn  :   Bl,  fus  ;  on  char,  sulph  odor.   Primr 

strat,  with  copper  ores. 
Magnetic  pyrites,  214.  3-5 — 4-5  VI ;  mas  ;    G  4-5 — 4-7 ;   broaze-yw,  copper-r  ;  St 

gyh-bfc ;  magnetic  ;  brittle  ;  dilute  nit  sol :    Bl, 

fas,  sulph  odor. 
Leucopyrite,          216.  5-0—5-5  HI ;  mas ;  G  7-2—7-4  ;  silver- w,  steel-gy  ;  St  gyh- 

bk  ;  brittle  :  Bl,  fus  ;  oa  ckar,  arsen  fumes. 
Capper  mckeV       244.        "        VI ;  mas  ;  G  7-3—7-7  ;  copper-r ;  St  pale  bnh-bk ; 

britfle  :   B$t  fus  !  on  char,  arsen  fumes.     Prita, 

usual  with  cobalt  ovcs*. 


TABLE  J.  FOR    DETERMINATION    OF    MINERALS.        401 

Hardness. 

Nickel  glance,  244.  5-0—5-5  I ;  inas ;  G  6—6-2 ;  silver  w,  steel-gy  ;  St  gyh-bk : 
Bl,  fus  !  dccrep  ;  sulph  and  arsen  fumes  in  glass 
tube. 

Cobaltine,  247.  "  I;  mas;  G  6-3— 64 ;  silver-w,  rdh ;  St  gyh-bk; 

brittle  :  Bl,  fus  ;  on  char,  arsen  fumes,  bh,  glob, 
mag ;  bar  blue.  Prim. 

Smaltine,  247.  "  I;  mas;  G  64—7-2;  tin-w,  steel-gy ;  St  gyh-bk; 

brittle  :  Bl,  fus !  arsen  odor,  gyh  bk  mag  pearl; 
bar  blue.  Prim, 

White  ir'n  pyrites,  214.  "  III ;  mas  ;  crests ;  G  4-6 — 4-9  ;  pale  bronze  yw  ; 
St  gyh,  bnh-bk ;  brittle  :  Bl,  fus  ;  on  char,  sulph 
fumes. 

Mispickel,  215.  5-5— £  0  UI ;  mas  ;  G  6-1 ;  eilver-w ;  St  dark  gyh-bk  ;  brit- 

tle :  Bl,  on  cAar,  arsen  fumes,  and  leaves  a  mag- 
netic globule 

Iron  pyrites,  212.  6-0—6.5  I ;  mas ;  G  43—5-1 ;  light  bronze-yw  ;  St  bnh-bk  : 

Bl,  fus ;  on  char,  sulph  odor.  Prim,  strat,  vole, 
etc. 


B.    STBEAK  METALLIC. 

*  Malleable. 

Native  mercury,    270.  fluid        G  13—14  ;  tin-w :  Bl,  volatilizes.     Strat,  prim. 
Native  lead,  260.  1-0—1-5  I ;  in  membranes  nnd  glob  ;  G 11—12  ;  lead  gray ; 

soils :  Bl,  fus !  !  volatilizes  and  colors  charcoal 

yellow. 
Native  copper,        273.  2-5—3-0  1 4  mas,  ia  strings ;  G  8-5— 8-6  ;  copper-r;  nit  sol! 

r  fumes ;  Bl,  fus,  colors  flame  green. 
Native  silver,          319.        "        I ;  mas,  capil ;  G  10—11 ;   silver-w  ;   nit  eo\ :  BL, 

fus. 

Native  gold,  311.        "        I ;  mas,  capil ;  G  12—20,  pale  to  deep  yw,  accord- 

ing to  the  proportion  of  silver  present ;  nit  not 

sol :  Bl,  fus. 
Native  platinum,    307.  4-0—4-5  In  grains  and  lumps  ;  Gr  16—19  ;  pale  steel  gy ;  hot 

nit-mur  sol :  Bl,  infus. 

Native  iron,  211.  4-0— 5*0  I ;  mas  ;  G  7 -3— 7-8  ;  iron-gy,  magnetic. 

Native  palladium,  310.  50—6-5  In  grains,    structure  rad ;    G  10—12 ;     steel-gy, 

eilver-w:  Bl,  infus. 

t  Not  malleable :  no  fumes  when  heated. 

Graphite,  91.  1-Q— 2-0  Mas,  fol !  gran  ;  G  2—2-1 ;  iron-bit,  dark  steel-gy ; 

sectile  ;  soils ;  nit,  no  action  :  Bl,  infus.  Prw*,' 
strat.  '  - 

nraenite,  222.  5-0—6-0  VI ;  mas ;  G  4-4—4-8  ;  dark  iron-bk ;  slightly  mag- 

netic ;  strong  mur  sol :  Bl,  infus.  Prim,  vole. 

}  Not  malleable  :  fumes  when  heated. 

Jfolybdenite,          298.  1-0—1-5  VI ;  mas,  fol !  lam  flex ;  G  4-5—4-8 ;  pure  lead-gy ; 
sectile  ;  nit,  partly  sol :  Bl,  infus,  on  shear  sulph 
odor.     Prim. 
34* 


402        TABLE   I.  FOR    DETERMINATION   OF   MINERALS, 

Hardness. 
Fol.  Tellurium,      263,  1-0— 1-5  H ;  fol  t  gran ;  6-  7—7-1 ;  bfeh  lead-gy ;  lam  fie*; 

sectile  ;  nit  sol !    Bl,  on  char,  w  fumes,  flame  b. 

Prim. 
Gray  antimony,     301.  2-0  III ;  cleav  ;  c&l,  div  ;  G  4-5 — 4-7 ;  lead-gy,  steel-gy  f 

ta nrishes  ;  lam  subtlcx :  Bl,  fas  ! }  011  ckar  sulpb 

odor  and  wholly  volat.     Prim. 
Vitreous  silver,      321.  2-0—2-5  I ;   maa,  retic  ;  G  7-1—7-4 ;  bkh  lead-gy ;   nit  sol : 

BIT  fas  !  !  imtum,  glob  of  silver.    Silver  ores. 
Native  tellurium,   300.        •*        VI ;  mas ;   G  5-7— 6-1 ;  tin-w,    rather  brittle :    Bi> 

fus !  !  on  char  gnh  flame,  w  inodorous  fumes, 

wholly  volat.    Prim. 
Brittle  silver,          322.        «*        III ;  ma*;  G  6>2 — &3 ;  iron-bk ;  eectile ;  ht»t  nit  sol  : 

Bl,  fus  f !  eulph  and  antim  fumes ;  on  char,  glob 

of  silver.     Silver  ores. 
Native  bismuth,     258,        •*       I;  mas,  cleav  !  G  9-7—9-8  ;  silver-w,  rdh  ;  nit  sol, 

aad  solution  w  if  diluted  :  Bl,  fas  !  J  volat,  inod  ; 

y  w  oa  char.     Prim. 
Vitreous  copper,    275.  2'5— 3O  III  r  mas  ;  G  5-5 — 5-8  ;  bkh,  lead-gy ;  nit  sol,  and 

polished  iron  put  in  the  solution  covered  with 

copper:  Blrfua  I  on  char  sulph  fames.  Prim,  stral. 
Galena,  260.  2-5—3-0  I ;  cleav  !  mas ;  G  7-5—7-7 ;  pure  lead-gy  ;  rather 

eecfcile  :  El,  fus !  decrep ;  on  char  sulph  fume» 

and  glob  of  lead.     Prim,  strat. 
Amalgam,  270.  20—3-5  I ;  mas ;  G  10-5 — 14 ;  silver-w  ;  nit  sol :  Bl,  fumes 

of  mercury,  and  silver  glob. 
Native  antimony,  301.  3-0— 3-5  VI ;  cleav  ;  lam,  mas  ;  G  6-6 — 6-8 ;  tin-w :  Bl,  fus  ! } 

volat ;  on  char  w  fumes.     Prim. 

Native  arsenic,       304.  3-5  VI ;  mas  ;  G  5-6—5-8 ;  tin-w,  lead-gy,  darker  from 

.  tarnish ;  brittle :   Bl,  wholly  volat,  garlic  odor. 

Prim, 
Gray  copper,          278.  3-0 — 4-0  I ;  tetrahed ;  mas  ,-  G  4-7 — S'l ;  steel-gy  to  iron-bk : 

Bl,  fus  ! !  arson  and  antim  fumes  ;  copper  reac- 
tion.   Prim,  copper  ores. 
White  nickel,         244.  5-0— 5-5  I  -,  mas ;  G  7-1—7-2 ;  tin-w :  Bl,  arsen  fumes ;  also 

nickel  reaction.   Prim. 

In  determining  the  name  of  a  mineral  by  the  preceding 
table,  trials  should  be  made  of  the  hardness  and  of  the  other 
characters  upon  which  the  arrangement  is  based,  as  shown 
in  the  general  view  on  page  188.  The  particular  subdi- 
vision containing  the  species  is  thus  arrived  at,  and  also,  by 
means  of  the  hardness,  the  place  of  the  species  in  the  sub- 
division. Afterwards,  by  a  comparison  of  the  other  charac- 
ters, (specific  gravity,  color,  etc.,}  with  the  brief  descriptions 
given  in  the  table,  the  name  of  the  mineral  will  be  ascer- 
tained. If  any  doubt  still  remains,  the  fuller  descriptions  in 
the  body  of  the  work  may  be  referred  to,  for  the  convenience 
of  which  reference,  the  page  is  added  for  each  species. 


TABLED.  FOR  DETERMINATION  OF  MINERALS.       403 

The  following  hints  may  be  of  service  to  the  beginner  in 
the  science,  by  enabliifg  him  to  overcome  a  difficulty  in  the 
outset,  arising  from  the  various  forms  and  appearance  of  the 
minerals  quartz  and  limestone.  Quartz  occurs  of  nearly 
every  color,  and  of  various  degrees  of  glassy  luster  to  a  dull 
stone  without  the  slightest  glistening.  The  common  grayish 
cobble  stones  of  the  fields  are  usually  quartz,  and  others 
are  dull  red  and  brown ;  from  these  there  are  gradual 
transitions  to  the  pellucid  quartz  crystal  that  looks  like  glass 
itself.  Sandstones  and  freestones  are  often  wholly  quartz, 
and  the  seashore  sands  are  mostly  of  the  same  material.  It  is 
therefore  probable  that  this  mineral  will  be  often  encountered 
in  mineralogical  rambles.  Let  the  first  trial  of  specimens 
obtained  be  made  with  a  file  or  the  point  of  a  knife,  or  some 
other  means  of  trying  the  hardness  ;  if  the  file  makes  no  im- 
pression, there  is  reason  to  suspect  the  mineral  to  be  quartz  ; 
and  if  on  breaking  it,  no  regular  structure  or  cleavage  plane 
is  observed,  but  it  breaks  in  all  directions  with  a  similar 
surface  and  a  more  or  less  vitreous  luster,  the  probability  is 
much  strengthened  that  this  conclusion  is  correct.  The 
blowpipe  may  next  be  used  ;  and  if  there  is  no  fusion  pro- 
duced  by  it,  when  carefully  used  on  a  thin  splinter,  there  can 
be  little  doubt  that  the  specimen  is  in  fact  quartz. 

Carbonate  of  lime  (calc  spar,  including  limestone,)  is 
another  very  common  species.  If  the  mineral  collected  is 
rather  easily  impressible  with  a  file,  it  may  be  of  this  species  : 
if  it  effervesces  freely  when  placed  in  a  test-tube  containing 
dilute  muriatic  acid,  and  is  finally  dissolved,  the  probability 
of  its  being  carbonate  of  lime  is  increased  :  if  the  blowpipe 
produces  no  trace  of  fusion,  but  a  brilliant  light  from  the 
fragment  before  it,  but  little  doubt  remains  on  this  point. 
Crystalline  fragments  break  with  three  equal  oblique 
cleavages. 

Familiarized  with  these  two  Protean  minerals  by  the  trials 
here  alluded  to,  the  student  has  already  surmounted  the  prin- 
cipal difficulties  in  the  way  of  future  progress.  Frequently 
the  young  beginner,  who  has  devoted  some  time  to  collecting 
all  the  different  colored  stones  in  his  neighborhood,  on  pre- 
senting them  for  names  to  some  practised  mineralogist,  is  a 
little  disappointed  to  learn  that,  with  two  or  three  exceptions, 
his  large  variety  includes  nothing  but  limestone  and  quartz. 
He  is  perhaps  gratified,  however,  at  being  told  that  he  may 
call  this  specimen  yellow  jasper,  that  red  jasper,  another 


404       TABLE    II.  FOR    DETERMINATION    OF    MINERALS. 

flint,  and  another  hornstone,  others  chert,  granular  quartz, 
ferruginous  quartz,  chalcedony,  prase,  smoky  quartz,  greasy 
quartz,  milky  quartz,  agate,  plasma,  hyaline  quartz,  quartz 
crystal,  basanite,  radiated  quartz,  tabular  quartz,  etc.  etc. ; 
and  it  is  often  the  case,  in  this  state  of  his  knowledge,  that 
he  is  best  pleased  with  some  treatise  on  the  science  in  which 
all  these  various  stones  are  treated  of  with  as  much  promi- 
nence as  if  actually  distinct  species  ;  being  loth  to  receive 
the.  unwelcome  truth,  that  his  whole  extensive  cabinet  con- 
tains only  one  mineral.  But  the  mineralogical  student  has 
already  made  good  progress  when  this  truth  is  freely  admit- 
ted, and  quartz  and  limestone,  in  all  their  varieties,  have 
become  known  to  him. 

To  facilitate  still  farther  the  study  of  minerals,  the  follow- 
ing tables  are  added. 


TABLE  II.  FOR  THE  DETERMINATION  OF 
MINERALS, 

The  general  arrangement  in  this  table  is  the  same  as  in 
the  preceding :  but  the  order  of  the  species,  instead  of  being 
that  of  their  hardness,  is  that  of  their  specific  gravity. 


I.— SOLUBLE  MINERALS. 

A.    No  EFFERVESCENCE  WITH  MUBIATIC  ACID. 

a.  Not  deflagrating  on  burning  coals. 


Glauber  salt 
Sal  ammoniac, 
Epsom  salt, 
Borax, 
Alum, 

Sp.  gr. 

1-4—  1-5 
1-5—  1-6 

1-7—  1-8 
u 

b 

Copperas, 
White  vitriol, 
Blue  vitriol, 
Common  salt, 
White  arsenic, 

Sp.  gr. 

2-0 
2-0—2-1 
2-2—  2-3 

« 

3-7 

Nit.  of  lime, 
Niter, 


b.  Deflagrate  on  burning  coals. 


1-62 
1-9— 2-0 


Nit.  of  soda, 


2-0— 3-0 


TABLE  '  II.  FOR    DETERMINATION  OF    MINERALS.       405 


B.    EFFERVESCING  WITH  MURIATIC  ACID. 


Natron, 


1-4— 1-5 


II.— INSOLUBLE    MINERALS. 

I.  LUSTER  UNMETALLIC. 

A.    STREAK  UNCOLORED. 

a.     No  fames  before  the  blowpipe  on  charcoal. 
Wholly  soluble  in  one  or  more  of  the  acids,  (cold  or  hot),  usually  with  effervescence. 

*  Infusible. 
Sp.  gr.  Sp.  gr. 

Websterite,  1-6—1-7  Magnesite,  2-9 — 3-0 

Brucite,  2-3—2-4  Mesitine  spar,  3-3—3-7 

Nemalite,  2-3 — 2-5  Diallogite,  3-5 — 3- 

Calc  spar, 

Hydromagnesite, 

Arragonite,  2-8—3-0  Blende,  4-0 — 4-1 

Dolomite, 


Wavellite, 

Boracite, 

Apatite, 

Fluor  spar, 

Cacoxene, 

Triplite, 


1-6—1-7 

Magnesite, 

2-3—2-4 

Mesitine  spar. 

2-3—2-5 

Diallogite, 

" 

Oligon  spar, 

,       2-8 

Yttrocerite, 

2-8—3-0 

Blende, 

2-8—2-9 

t  Fusible  with  more  or  less  difficulty. 

2-3—  _2-4 

Strontianite, 

2-9—3-0 

Spathic  iron, 

3-0—3-3 

Troostite, 

3-1—3-2 

Witherite, 

3-3—3-4 

White  lead  ore, 

3-4__3-8 

Pyromorphite, 

3-6—3-7 
3-7—3-9 
4-0 — 4-1 

4-2 — 4-4 
6-1—6-5 
6-5—7-1 


I 
2.    Soluble  in  acids,  excepting  the  silica,  which  separates  as  a  jelly. 

*  Infusible. 


Allophane, 


1-8—1-9  1  Halloylite, 


1-8—2-1 


t  Fusible. 


2-0—2-2 


2-0—2-3 

H 

2-1—2-3 
2-2 — 2-3 
2-2—24 


Me  sole, 


Philippsite, 

Analcime, 

Datholite, 

Natrolite, 

Scolecite, 

Laumonite, 

Dysclasite, 

3.    Not  acted  on  by  acids,  or  partially  soluble  without  forming  a  jetty. 
*  Infusible. 

Chrysocolla,  2-3—2-4 1  Yenite,          2-4—5.2 


Thorn  sonite, 

Sodalite, 

Pectolite, 

Tabular  spar, 

Electric  calamine,    3-2 — 3-5 


2-3—2-4 
ii 

2-2—2-5 

2-69 

2-7_2-9 


406       TABLE    II.  FOR  DETERMINATION    OF    MINERALS. 


Opal, 
Quartz, 

Sp.  gr. 

|£ 

2-6—2-8 

Topaz, 
Diamond, 

Sp.gr. 

3-4—36 
3-4—3-7 

Alum-stone, 

H 

Kyanite, 

3-5—3-7 

Talc, 

2-7—2-9 

Staurotide, 

3-5—3-8 

Pyrophyllite, 

M 

Chrysoberyl, 

3-5—3-8 

Mica, 

2-8—3-0 

Anatase, 

3-8—3  9 

Turquois, 

u 

Sapphire, 

3-9—4-2 

Nephrite, 

2-9—3-1 

Blende, 

4-0—4-1 

Andalusite, 

2-9—3-2 

Spinel, 

3-5  —  4-6 

Green  hyd.  nickel, 

3-05 

Zircon, 

4.4__4-8 

Clintonite, 

3-0—3-1 

Monazite, 

4-8—5-1 

Sillimanite, 

^.0—3-4 

Piumbo-resinite, 

6-3—6-4 

Bucholzite, 

3-2—3-6 

Tin  ore, 

6-5—7-1 

Chrysolite, 

3-3—3-6 

t  Fusible  with  more  or  less  difficulty. 

Chabazite, 

2-0—2-2 

Prehnite, 

2-8—3-0 

Stilbite, 

2-1—2-2 

Boracite, 

2-9—3-0 

Heulandite, 

2-2 

Chrysolite, 

u 

Gypsum, 

2-2—2-4 

Euclase, 

2-9—3-1 

Apophyllite, 

2-3—2-4 

Hornblende, 

2-9—3-4 

Feldspar, 

2-3  —  2-6 

Lazulite, 

3-0—3-1 

Serpentine, 

2-4—2-6 

Tourmaline, 

M 

Obsidian, 

2-2—2-8 

Spodumene, 

3-1—3-2 

Harmotome, 

2-3—2-5 

Chondrodite, 

(4 

Petalite, 

2-4—2-5 

Axinite, 

3.2—3-3 

Schiller  spar, 

2-5—2-7 

Pyroxene, 

3-1—3-5 

Lapis  Lazuli, 

2-5—2-9 

Sphene, 

3-2—3-5 

Albite, 

2-6—2-7 

Epidote, 

u 

Labradorite, 

2-6—2-8 

Idocrase, 

3-3—3-4 

Scapolite, 

u 

Manganese  spar, 

3.4—3.7 

lolite, 

M 

Garnet, 

3-5—4-3 

Beryl, 

tl  ' 

Celestine, 

3-8—4-0 

Chlorite, 

2-6—29 

Pyrochlore, 

3-8—4-3 

Chlorophyllite, 

2-7—2-8 

Heavy  spar, 

4-3—4-8 

Talc, 

2-7—2-9 

Monazite, 

4-8—5-1 

Mica, 

2-8—3-0 

Tungstate  of  lime, 

6-0—6-1 

Anhydrite, 

"          Anglesite,** 

6-2—6-3 

b.     Colored  or  odorous  fumes  before  the  blowpipe. 

Scorodite, 

3-1  —  3-3  |  Horn  silver, 

5-5—5-6 

Blende, 

4-0  —  4-1    Bismuth  blende, 

5-9—6-1 

Calamine, 

4-2  —  4-5  1  Mimetene, 

6  4—6-5 

TABLE    II.  FOR    DETERMINATION    OF    MINERALS.       407 


B.     STREAK  COLORED. 

a. 

No  fumet  before  the  blowpipe. 

*  Fusible. 

Sp.  gr. 

Sp.  gr. 

Vivianite, 

2-6—2-7 

Pyrochlore, 

4-2  —  4-3 

Uranite, 

3-0—3-6 

Minium, 

4-6 

Chondrodite, 

3*1—3-3 

Monazite, 

4-8—5-1 

Allanite, 

3-2  —  4-1 

Cupreous  anglesite, 

5.3—5-5 

Triplite, 

3-4—3-8 

Red  copper  ore, 

5.9—6-0 

Azurite, 

3.5—3.9 

Chromate  of  lead, 

6-0 

Green  malachite, 

4-0  —  4-1    Pyromorphite, 

6-8—  7-1 

t  Infusible. 

Sulphur, 

2-07 

Blende, 

4-0—4-1 

Copper  mica, 

2-55 

Psilomelane, 

4-0—4-4 

Earthy  cobalt, 

2-2  —  2-3 

Rutile, 

4-2  —  4-3 

Cobalt  bloom, 

2-9—3-0 

Chromic  iron, 

4-3—4-5 

Warwickite, 

3-0—3-3 

Atacamite, 

4.4—4.5 

Dioptase, 

3-2—3-3 

Red  antimony, 

4.4  —  4-6 

Cacoxene, 

3.3—3.4 

Red  zinc  ore, 

5-4—5-6 

Orpiment, 

3-4—3  5 

Red  silver  ore, 

5.4—5.9 

Realgar, 

3.3—3-7 

Pitchblende, 

6-47 

Wad, 

3-7 

Tin  ore, 

6-5—7-1 

Black  copper, 

Cinnabar, 

8-0—8-1 

Brown  hematite, 

3-9—  4-1 

LUSTER  METALLIC. 

A.    STREAK  UNCOLORED. 

*  No  fumes  before  the  blowpipe  on  charcoal. 

Earthy  cobalt,  2-2 — 2-3   Specular  iron,  4'5 — 5-3 

Wad,  3-7  Pyrolusite,  4-8—5-0 

Yenite,  3-8—4-1    Franklinite,  4-8—5-1 

Arkansite,  3*85  Magnetic  iron  ore,  5*0 — 5*1 

Brown  hematite,       3-9 — 4-0   Columbite,  5-9 — 6-1 

Blende,  4-0—4-1    Pitchblende,  6-47 

Psilomelane,  4-0—4-4    Wolfram,  7-1—7-4 

Manganite,  4-3—4-4   Cinnabar,  8-0—8-1 

Chromic  iron,  4*3 — 4'5 


408        TABLE  III.  FOR  DETERMINATIONOF  MINERALS. 


t  Fumes  before  the  blowpipe. 


Copper  pyrites,  4-0 — 4 -2 

Magnetic  pyrites,  4'5 — 47 
White  iron  pyrites,          ** 

Iron  pyrites,  4*8 — 5-1 

Variegated  copper,  5'0 — 5'1 

Dark  red  silver.  5-7 — 5-9 


Nickel  glance, 

Mispickel, 

Cobaltine, 

Smaltine, 

Leucopyrite, 

Copper  nickel, 


B.    STREAK  METALLIC. 

*  Malleable. 

Native  iron, 
Native  copper, 
Native  silver, 
Native  palladium, 

Sp.  gr. 

7-3—7-8 
8-5—8-6 
10—11 
10—12 

Native 
Native 
Native 
Native 

t  Not  malleable  :  no  fumes  when  heated. 

Graphite,  2-21         |  Ilmeiiite, 

J  Not  malleable  :  fumes  when  heated  on  charcoal. 


Gray  antimony, 
Molybdenite, 
Gray  copper, 
Vitreous  copper, 
Native  arsenic, 
Native  tellurium, 
Brittle  silver, 


4-5—4 
4-5—4- 
4-7—5 
5-5—5 
5-6—5 
5-7—6 
6-2—6 


Native  antimony, 
Fol.  tellurium, 
White  nickel, 
Vitreous  silver, 
Galena, 

Native  bismuth, 
Amalgam, 


6-0—6-2 

6-1 

6-2-6-4 

6-4—7-2 

7-2—7-4 

7-3—7-7 


Sp.  gr. 

11—12 
13—14 
16—19 
12—20 


4.4—4.8 


6-6—6-8 
7-0—7-1 
7-1—7-2 
7-1—7-4 

7.5—7.7 

9-7—9-8 
10-5—11 


TABLE  III.— MINERALS  ARRANGED  ACCORDING 
TO  THEIR  CRYSTALLIZATION. 

I  .—CRYSTALS  MONOMETRIC. 
A.     Luster  unmetallic. 

*  Infusible. 
Hardness.  Sp.  gr.  Cleavage. 

Blende,  250  2-0—3-0  4-0—4-2  Dodecahedral. 

Chromic  iron,  222  5'5  4-3 — 4-5  Octahed.  imperf. 

Leucite,  175  5-5—6-0  2-4 — 2-5  Ncne. 

Dysluite,  161  7-5—8-0  4-5—4-6  Oct.  imp. 

Spinel,  160  8-0  3-5— 3'6  Oct.  imp. 

Diamond,  80  10*0  Oct.  perfect. 


TABLE    III.  FOR  DETERMINATION  OF  MINERALS.        409 


t  Fusible. 


Alum, 

Common  salt, 
Red  copper  ore, 
Fluor  spar, 
Pyrochlore, 
Analcime, 
Lapis  Lazuli, 
Sodalite, 
Garnet, 
Boracite, 


Hardness. 

127  1-5— 2-0 
104  2-0 
279  3-5—4-0 
121  4-0 

5.0—5-5 

H 

5.5—6.0 

5-5—6-0 
6-5— 7-5 


208 
168 
196 
197 
184 


126  7-0 


Sp.  gr. 
1-7—1-8 
2-2 — 2-3 
5-8—6-1 
3-0—3-3 
3-8— 4-5 
2-0—2-3 
2-5—2-9 
2-2—2-4 
3.5 — 4.3 

2-9—3-0 


Cleavage.. 

Oct. 
Cubic. 
Oct.  imperf. 
Oct.  perf. 
None. 
Imperfect. 
Dodec.  imperf. 
Dodec.  imp. 
Dod.  oft.  distinct 
Oct.  indistinct. 


2. — Luster  metallic. 

*  No  fumes  before  the  blowpipe  on  charcoal 

Native  copper,  273  2'5 — 8-0     8-4 —  8-8  None. 

Native  silver,  319         "         10-3 — 10-5  None. 

Native  gold,  311         "         12-0—20-0  None. 

Blende,  250  3-5—4-0     4-0—  4*2  Dodec.  perf! 

Native  platinum,  307  4*0 — 4-5  16-0 — 19-0  Cubic,  indist. 

Native  iron,  211  4-5  5-1 —  5-2  Oct.  perfect. 

Chromic  iron,  222  5-Q — 5-5     4-3 —  4-5  Oct.  imp. 

Franklinite,  221  5-5—6-5     4-8 —  5-1  Oct.  imp. 

Magnetic  iron,  216         "  5-0 —  5-1  Oct.  imp. 

t  Fumes  before  the  blowpipe  on  charcoal. 


Vitreous  silver, 
Native  bismuth, 
Native  amalgam, 
Var.  copper  ore, 
Galena, 
Gray  copper  ore, 
Nickel  glance, 
Cobaltine, 
Smaltine, 
White  nickel, 
Pyrites, 

321 
258 
270 
277 
260 
278 
244 
247 
247 
244 
212 

2-0—2 
ii 

2-0—3 

2-5—3 

(t 

3-0—4 
5-0—5 

M 
« 

5-5 

6-0—6 

•5 

•5 

•0 

•0 
•5 

•5 

7 

9 
10 
5 
T 
4 
6 
6 
6 
1' 
4 

•1—7-4 
•7—9-8 
•5—14 
•0—5-1 
•5—7-7 
•7—5-2 
•0—6-2 
1—  -6-3 
•3—6-4 
1—7-2 
•8—5-1 

Dodec.  imperf. 
Oct.  perf! 
Dodec.  imp. 
Oct.  imp. 
Cubic  perf! 
Indistinct. 
Cubic  perf! 
Cubic  perf. 
Oct.  imp. 

Cubic  imp. 

Anatase, 


H.— CRYSTALS  DIMETRIC. 
1.     Luster  unmetdllic. 

*  Infusible. 

292  5-5—6-0  3-8—3-9  Oct.  and  basal. 
35 


410     TABLE  in.  FOR  DETERMINATION  OF  MINERALS. 

Hardness.          Sp.  gr.  Cleavage. 

Tin  ore,  295  6-0—7-0  6-5—7-1  Indistinct. 

Zircon,  200  7-5  4-4 — 4'8  Imperfect. 

t  Fusible. 

Uranite,  210  2-0—2-5  3-0—3-6  Basal,  perf  !! 

Apophyllite,  165  4-5—5-0  2-2—2-4  Basal,  perf! 

Scapolite,  180  5-0 — 6-0  2-5 — 2-8  Lat.  distinct. 

Idocrase,  184  6'0 — 6-5  3'3 — 3-5  Lat.  indistinct 

Rutile,  291  "         4-1 — 4-3  Lat.  imp. 

2.     Luster  metallic. 

Foliated  tellurium,  263  1-0—1-5  7-0—7-2  Foliated! 
Copper  pyrites,       275  3-5 — 4-0  4-1—4-2  Indistinct. 
Hausmannite,         242  5-0 — 5-5  4-7 — 4-8  Basal,  distinct ! 
Braunite,  242  6-0 — 6-5  4*8 — 4'9  Oct.  distinct. 

III.    CRYSTALS  TRIMETRIC. 
1.     Luster  unmetallic. 

*  Infusible. 

Talc,  143  1-0—1-5  2-7—2-9  Basal,  fol !! 

Arragonite,  118  3-5—4-0  2-9 — 3-0  Lat.  imp. 

Red  Zinc  ore,  251  4'0— 4-5  5-4 — 5-6  Basal,  fol !! 

Chrysolite,  156  6-5—7-0  3-3—3-5  Lat.  imp. 

Staurotide,  174  7-0—7-5  3-6—3-8  Indistinct. 

Andalusite,  174  7-5  3-1 — 3-4  Indistinct. 

Topaz,  194  8-0  3-4—3-6  Basal,  perfect! 

Chrysoberyl,  199  8-5  3-5 — 3-8  Imperfect. 

t  Fusible :  gelatinize  in  acids . 

Mesole,  167  3-5  2-3—2-4  One  perfect. 

Thomsonite,  167  4-5  2-2 — 2-4  Two  rect.  perf. 

Phillipsite,  168  4-0—4-5  2-0—2-2  Imperfect. 

Electric  calamine,  253  4-5 — 5-0  3-3 — 3-5  Lat.  perfect. 

Natrolite,  166  4'5— 5-5  2-1—2-3  Lat.  perf. 

Scolecite,  167  5-0 — 5-5  2-2 — 2-3  Imperfect. 

J  Fusible :  not  gelatizing ;  giving  no  odorous  or  colored  fumes  before  the 
blowpipe. 

Talc,  (some  var.,)  143  1-0—1-5  2-7—2-9  Foliated!! 

Niter,  101  2-0  1'9 — 2-0  Imperfect. 

Epsom  salt,  124  2'0 — 2-5  1-7 — 1-8  One  perfect. 

Cryolite,  132         "  2*9—3-0  One  prf;  two  imp. 


TABLE  JH.  FOR  DETERMINATION  OP  MINERALS.        411 


Mica,  (Rhombic,) 

Hardness.          Sp.  gr.               Cleavage. 

193         "         2-8-—  3-1  Foliated!! 

Anglesite, 

264  2-5—3-0  6-2-^6-3  Imperfect. 

Heavy  spar, 

108  2-5  —  3-5  4-3  —  4-8  Imperfect. 

Celestine, 

110         "         3-9—4-0  Lat.  distinct. 

Anhydrite, 

114  3-0—3-5  2-8—3-0  Three  rect.  dist. 

White  lead  ore, 

264         "         6-1—6-5  Lat.  perf. 

Witherite,  . 

109         "         4'2  —  4-4  Imperfect. 

Serpentine, 

145  3-0—4-0  2-5  —  2-6  Sometimes  fol. 

Strontianite, 

Ill  3-5  —  4-0  3-6—3-8  Lat.  distinct. 

Wavellite, 

130         "         2-2—2-4  Two  distinct. 

Stilbite, 

165         "         2-1—  2-2  One  perfect! 

Harmotome, 

168  4-0  —  4-5  2-4—2-5  Imperfect. 

Wolfram, 

225  5-0—5-5  7-1—7-4  One  perfect. 

Lazulite, 

131  5-0  —  6-0  3-0  —  3-1  Indistinct. 

Yenite, 

226  5-5—6-0  3-8—4-1  Indistinct. 

Prehnite, 

170  3-0  —  7-0  2-8  —  3-0  Basal,  distinct. 

lolite, 

190  7-0—7-5  2-5—2-7  Indistinct. 

§  Giving  fumes  before  the  blowpipe  on  charcoal 


Orpiment, 
Sulphur, 
White  vitriol, 
White  antimony, 
Atacamite, 
Scorodite, 


305  1-5—2-0  3-4—3-6  Foliated! 

98  1-5 — 2-5  2-0 — 2-1  Indistinct. 

252  2-0—2-5  2-0—2-1  One  perfect. 

303  2-5 — 3-0  5-5 — 5-6  Lat.  perfect !! 


285  3-0—3-5 
230  3-5 — 4-0 


4-0 — 4.4 
3-1—3-3 


Basal,  perfect. 
Imperfect. 


2.     Luster  metallic. 


*  No  fumes  before  the  blowpipe  on  charcoal. 

Pyrolusite,  240  2-0—2-5  4-8 — 5-0  Three  imperfect. 

Manganite,  242  4-0 — 4-5  4-3 — 4*4  One  imperfect. 

Wolfram,  225  5-0—5-5  7-1—7-4  One  perfect. 

Yenite,  226  5-5 — 6-0  38 — 4-1  Indistinct. 

Columbite,  224  5-0 — 6*0  5*9 — 6-1  Indistinct. 

Ferrotantalite,  225         "         7-2 — 8-0  Imperfect. 

t  Fumes  before  the  blowpipe  on  charcoal. 


Gray  antimony,      301  2-0 
Brittle  silver  ore,  322  2-0—2-5 
Vitreous  copper,    275  2-5 — 3-0 
Leucopyrite,  216  5-0 — 5-5 

Mispickel,  215  5-0—6-0 

White  iron  pyrites,  214  6*0 — 6*5 


4.5 — 4-7  One  perfect ! 
6-2 — 6-3  Imperfect. 
5-5 — 5-8  Lat.  indistinct. 
7-2 — 7-4  One  distinct. 
6-1 — 6-2  Lat  imperfect. 
4-6 — 4-9  Lat  imperfect. 


412       TABLE  III.  FOR  DETERMINATION  OF  MINERALS. 


IV.—  CRYSTALS  MONOCLINATE. 

1. 

Luster  unmetallic. 

*  Soluble. 

Hardness.          Sp.  gr. 

Cleavage. 

Natron, 

103 

1-0—  1-5  1-4—  1-5 

Glauber  salt, 

102 

1-5—  2-0  1-5—2-0 

Copperas, 

227 

2-0            1-8—1-9 

One  perfect. 

Borax, 

107 

2-0—2-5  1-7 

Lat.  perfect. 

t  Insoluble  : 

no  fumes  before  the  blowpipe  on  charcoal. 

Vivianite, 

229 

1-5  —  2-0  2-6  —  2-7 

Basal,  perfect  ! 

Gypsum, 

112 

2-0             2-3—2-4 

Foliated  ! 

Mica, 

191 

2-0  —  2-5  2-8  —  3-0 

Foliated  !! 

Heulandite, 

164 

3-5  —  4-0  2-1  —  2-2 

Foliated. 

Laumonite, 

166 

3.5  —  4-0  2-3 

One  distinct. 

Green  malachite, 

281 

4-0—4-1 

Basal,  perfect. 

Azurite, 

283 

3-5—4-5  3-5—3-9 

Lateral. 

Clintonite, 

148 

4-0  —  5-0  3-0  —  3-1 

Foliated. 

Monazite, 

206 

5-0            4-8—5-1 

Basalt,  perfect  ! 

Datholite, 

142 

5-5  —  6-0  2-9—3-0 

Indistinct. 

Sphene, 

292 

3-2—3-5 

Indistinct. 

Hornblende, 

152 

5-0—6-0  2-9—3-4 

Lat.  perfect. 

Pyroxene, 

150 

«         3-2—3-5 

Lat.  distinct. 

Allanite, 

207 

«         3-3  —  3-8 

Indistinct. 

Feldspar, 
Chondrodite, 

176 
157 

6-0            2-3—2-6 
6-0—6-5  3-1—3-2 

One  prf  ;  one  imp. 
Indistinct. 

Epidote, 

182 

6-0  —  7-0  3-2—3-5 

Lat.  imperf. 

Spodumene, 

181 

6-5—7-0  3-1—3-2 

Lat.  perfect. 

Euclase, 

199 

7-5            2-9—3-1 

Basal,  perfect. 

f  Fumes  before  the  blowpipe. 

Cobalt  bloom, 

248 

1-5—  2-0  2-9—3-0 

Basal,  perfect  ! 

Realgar, 

305 

«         3-3—3-6 

Imperfect. 

Pharmacolite, 

305 

2-0—2-5  2-6—2-8 

Basal,  perfect  !! 

Miargyrite, 

323 

"         5-2—5-4 

Lat.  imperfect, 

2. 

Luster  metallic. 

Miargynte, 

323 

2-0—2-5  5-2—5-4 

Lat.  imperfect, 

Wolfram, 

225 

5-0—5-5  7-1—7-4 

One  perfect. 

Warwickite, 

293 

5-5—6-0  3-0—3-3 

One  perfect. 

Allanite, 

207 

«         3.3—3.  g 

Imperfect. 

Blue  vitriol, 


V.— CRYSTALS  TRICLINATE. 

*  Soluble. 

280  2-5  2-2—2-3  Imperfect, 


TABLE  III.  FOR  DETERMINATION  OF  MINERALS.       413 

t  Insoluble:  fusible. 
Hardness.          Sp.  gr.  Cleavage. 

Tabular  spar,  141  4-0 — 5-0  2-7—2-9  One  perfect. 
Albite,  177  6-0  2-6—2-7  One  perf.  ;  two 

imperfect. 
Labradorite,  178  "  2-6 — 2-8  One  perf.;  one 

imperfect. 

Manganese  spar,  239  6-0 — 7-0  3-4 — 3*7  One  perfect. 
Aximte,  190  6'5— 7-0  3-2 — 3-3  Imperfect. 

J  Infusible. 

Kyanite,  173  5-0—7-0  3-5—3-7  Lat.  distinct 

Sillimanite,  172  7-0—7-5  3-2—3-3  Diagonal  perf.!! 


6.     CRYSTALS  HEXAGONAL  OR  RHOMBOHEDRAL. 
1.     Luster  unmetallic. 

*  Soluble. 


Nitrate  of  soda, 

103 

1-5—2-0 

2-0—2-1 

Rhomb,  perf. 

Coquimbite, 

227 

u 

Hexag.  imperf. 

t  Insoluble  :  infusible. 

Brucite, 

126 

1-5 

2-35 

Foliated  ! 

Mica,  (hexagonal) 

193 

2-0—2-5 

2-8—3-1 

Foliated  !! 

Calc  spar, 

115 

2-5—3-5 

2-5—2-8 

Rhomb,  perf! 

Diallogite, 

242 

3-5 

3.5—3.6 

Rhombohedral. 

Magnesite, 

124 

3-0—4-0 

2-8  —  3-0 

Rhomb,  perf. 

Ankerite, 

120 

it 

2-9—3-2 

Rhomb,  perf. 

Dolomite, 

118 

3.5—4.0 

3-5—4-0 

Rhomb,  perf. 

Spathic  iron, 

228 

M 

3.7—3.9 

Rhomb,  perf. 

Alum  stone, 

129 

5-0 

2-6—2-8 

Basal,  near  perf. 

Dioptase, 

284 

u 

3-2—3-3 

Rhombohedral. 

Quartz, 

132 

7-0 

2-6—2-7 

Imperfect. 

Sapphire, 

158 

9-0 

3-9 

Basal,  perf. 

J  Insoluble  :  fusible,  without  fumes. 

Chlorite, 

145 

1-5—2-0 

2-6—2-9 

Foliated  ! 

Chlorophyllite, 

162 

1-5—3-5 

2-7—2-8 

Basal,  fol. 

Chabazite, 

169 

4«0  —  4-5 

2-0—2-2 

Rhombohed.  ind. 

Apatite, 

120 

5-0 

3-0  —  3-3 

Indistinct. 

Troostite, 

240 

5-5 

4-0  —  4-1 

Lat.  perf. 

Nepheline, 

179 

5.5—6-0 

2-4—2-7 

Imperfect. 

Tourmaline, 

187 

7-0—  8-0 

3-0—3-1 

Indistinct. 

Beryl, 

197 

7-5—8-0 

2  6—2-8 

Basal,  indistinct. 

35* 

414       TABLE  III.  FOR  DETERMINATION  OF  MINERALS. 

§  Insoluble :  fumes  before  the  blowpipe  on  charcoal. 

Hardness.         Sp.  gr.  Cleavage. 

Red  silver  ore,  323  2-0 — 3-0  5-4 — 5*9  Imperfect. 
Cinnabar,  270  2'0 — 2-5  7-8 — 8-1  Hexag.  perfect. 

Calamine,  253  5-0  4-3 — 4-5  Rhomb,  perf. 

2.     Luster  metallic. 

*  No  fumes  before  the  blowpipe  on  charcoal. 

Graphite,  91  I'O — 2'0  2-0—2-1   Foliated! 

Ilmenite,  222  5-0—6-0  4-4—5-0  Indistinct. 

Specular  iron,        218  5-5—6-5  5*0 — 5-3  Indistinct. 

t  Fumes  before  the  blowpipe  on  charcoal. 

Molybdenite,  298  1-0—1-5  4-5—4-8  Foliated  !! 
Native  tellurium,  300  2-0—2-5  5-7—6-1  Imperfect. 
Dark  red  silver,  323  2-5  5-7 — 5-9  Imperfect. 

Cinnabar,  270         "         7-8—8-1  Hexag.  perfect. 

Native  antimony,  301  3'0 — 3'5  6-6 — 6-8  Basal,    perfect ! 

rhombohed.  dist. 

Native  arsenic,      304  3-5  5-6 — 6*0  Imperfect. 

Magnetic  pyrites,  214  3-5 — 4-5  4*6 — 4-7  Basal  hexag.  prf. 
Copper  nickel,       244  5-0—5-5  7-3—7-7 


INDEX. 


A. 

ACADIOLITE,  170. 

Acbmite,  157,  (Acmite.) 
Acid,  Arsenous,  305. 

Boracic,  107. 

Carbonic,  93. 

Hydrochloric,  77. 

Muriatic,  77. 

Sulphuric,  99. 

Sulphurous,  99. 

Tungstic,  299. 
Acmite,  157. 
Actinolite,  153. 
Adamant,  80,  (Diamond.) 
Adamantine  spar,  158. 
Adulaiia,  176. 
^Eschynite,  202. 
Agalmatolite,  342. 
Agaric  mineral,  116,  (Calc  Tufa.) 
Agate,  135. 
Alabandine,  242. 
Alabaster,  113. 
Alalite,  151. 
Albite,  177. 
Alexandrite,  199. 
Allagite,  239. 
Allanite,  207. 
Allophane,  162. 
Alluaudite,  230. 
Almandine,  185. 
Alum,  127. 

Manufacture  of,  128, 129. 
ALUMINA,  127,  158. 
Alumina,  Fluate  of,  132. 

Hydrate  of,  131,  132. 

Mellate  of,  132. 

Phosphate  of,  130. 

Sulphates  of  127,  128,  129. 
Alum  stone,  129. 
Alum  slate,  128. 
Aiuminite,  129. 
Aluminium,  Fluorid  of,  132. 
Amalgam,  Native,  270. 
Amber,  93. 
Amblygonite,  132. 


Amethyst,  134. 

Oriental,  158. 
Amianthus,  154. 
Ammonia,  Salts  of,  100. 

Carbonate  of,  101. 

Muriate  of,  100. 

Phosphate  of,  101. 

Sulphate  of,  101. 
Ammoniac,  Sal,  100. 
Amoibite,  244. 
Amphibole,  154. 
Amygdaloid,  339. 
Aualcime,  168. 
Anatase,  292. 
Ancramite,  257. 
Andalusile,  174. 
Andesin,  177,  (Albite. 
Anglarite,  230. 
Anglesite,  264. 

Cupreous,  264. 
Anhydnte,  114. 

Anhydrous  sulphate  of  lime,  114. 
Ankerite,  120. 
Anorthite,  178. 
Anthophyllite,  156. 

Hydrous,  171. 
Anthosiderite,  226. 
Anthracite,  85. 
Anthraconite,  117. 
Antigorite,  149. 
Antimonate  of  lime,  303. 
Antimonial  copper,  278. 

nickel,  244. 

silver,  322,  323. 
ANTIMONY,  301. 
Antimonophyllite,  303. 
Antimony,  Native,  401. 

Arsenical,  302. 

Feather  ore  of,  302. 

Gray,  301. 

Red,  303. 

Sulphuret  of,  301. 

White,  303. 

Antimony  and  lead,  sulphureta  of, 
302. 


416 


INDEX. 


Antimony  ores,  general  remarks 

on,  303. 

Antrimolite,  171. 
Apatelite,  228. 
Apatite,  120. 
Aphanesite,  284. 
Aphrodite,  148. 
Aplome,  186. 
Apophyllito,  165. 
Aquamarine,  198. 
Arendalite,  182,  (Epidote.) 
Arfvedsonite,  157. 
Argent,  French  for  silver. 
Argentine,  116. 
Argillaceous  shale,  341. 
Argillite,  341. 
Arkansite,  209. 
Arquerite,  270. 
Arragonite,  118. 
Arsenate  of  iron,  230. 

of  nickel,  245. 

of  cobalt  248. 

of  copper,  284. 

of  lime,  305. 
ARSENIC,  304. 
Arsenic,  Native,  304. 

Sulphurets  of,  305. 

White,  305. 
Arsenic  ores,  general  remarks  on, 

306. 
Arsenical  cobalt,  247. 

iron  pyrites,  215. 

lead,  263. 

manganese,  242. 

nickel,  244. 

silver,  322. 
Arsenous  acid,  305 
Asbestus,  151,  154. 
Asparagus  stone,  120. 
Aspasiolite,  163. 
Asphaltum,  95. 
Asteria,  158. 
Atacamite,  285. 
Atmospheric  air,  76. 
Augite,  150,  151. 
Aurichalcite,  254. 
Auriferous  pyrites,  213. 
Aurotellurite,  319. 
Automolite,  161. 
Aventurine  quartz,  134. 

feldspar,  176. 
Axinite,  190. 


Azure,  250. 
Azurite,  283. 


B. 


Babingtonite,  157. 
Balas  ruby,  160. 
Baltirnorite,  146. 
Bamlite,  329. 
BARYTA,  108. 
Baryta,  Carbonate  of,  109. 

Sulphate  of,  108. 

Sulphate-carbonate  of,  110. 
Baryt-Harmotome,  168,  (Harmo 

tome.) 

Barytocalcite,  110. 
Basalt,  339. 
Basanite,  137. 
Beaumontite,  285. 
Bell  metal,  290. 
Bell  metal  ore,  294. 
Beraunite,  230. 
Berengelite,  97. 
Beryl,  197. 
Berthierite,  302. 
Berzeline,  329. 
Beudantite,  329. 
Biddery  ware,  257. 
Biotine,  178,  (Anorthite.) 
BISMUTH,  257. 
Bismuth,  alloys  of,  259. 

Native,  258. 

Acicular,  258. 

Carbonate  of,  258. 

Cupreous,  258. 

Silicate  of,  258. 

Sulphuret  of,  258. 

Telluric,  258. 
Bismuth  blende,  258. 

nickel,  245. 

ocher,  258. 
Bismutite,  258. 

Bitter  spar,  119,  (Brown  Spar.) 
Bitumen,  95. 

Elastic,  94. 
Butuminous  coal,  85. 
Black  copper,  279. 

cobalt,  248. 

lead,  91. 
Black  jack,  251. 
Blei,  German  for  lead. 
Blende,  250. 
Bloodstone,  137. 
Blue  asbestus,  227. 


INDEX. 


417 


Blue  copper  ore,  283. 

iron  earth,  230 

malachite,  283,  (azurite.) 

spar,  !31,(Lazulite.) 

vitriol,  280. 
Bodenite,  208. 
Bog  iron  ore,  220. 

manganese,  241. 
Bole,  162. 
Boltonite,  157. 
Bones,  composition  of,  120. 
Boracic  acid,  107. 
Boracite,  126. 
Borate  of  lime,  123. 

of  soda,  107. 

of  magnesia,  126. 
Borax,  107. 

Borosilicate  of  lime,  142. 
Botryolite,  142. 
Boulangerite,  302. 
Bournonite,  278. 
Branchite,  97. 
Brass,  256, 290. 
Braunite,  242. 
Breccia,  344. 
Breccia  marble,  350. 
Breislakite,  157. 
Breunnerite,  229. 
Brevicite,  167. 
Brewsterite,  164. 
Britannia  metal,  304. 
Brittle  silver  ore,  322. 
Brocatello  di  Siena,  349- 
Brochantite,281. 
Bromic  silver,  324. 
Bromlite,  110. 
Bronze,  289,  290. 
Bronzite,  151. 
Brookite,  292. 
Brown  iron  ore,  220. 

hematite,  220. 

ocb^r,  220. 

spar,  119,229. 
Brucite,  126. 

see  chondrodite,  157. 
Bucholzite,  172. 
Bucklandite,  183. 
Buhrstone,  343,  346. 
Building    stone,    336,    337,    339, 

345. 

Buratite,  285. 
Sustamite,  240. 


C. 

Cacholong,  139. 
Cacoxene,  230. 
Cadmia,  257. 
CADMIUM,  257. 
Cairngorum  stone,  134. 
Calaite,  130,  (Turquois.) 
Calamine,  253. 

Electric,  253. 
Calcareous  spar,  115. 

tufa,  116. 
Calcedony,  135. 
Calcite,  115. 
Caledonite,  266. 
Callais,  131. 

Canaanite,  180,  (Scapolite.) 
Cancrinite,  180. 
Caoutchouc,  mineral,  94. 
Capillary  pyrites,  245. 
CARBON  and  compounds  of  car- 
bon, 80. 

Carbonic  acid,  93. 
Carbuncle,  187. 
Carbureted  hydrogen,  77* 
Carburet  of  iron,  91. 
Carnelian,  135. 
Carpholite,  171. 
Carphosiderite,  230. 
Ca.-tor,  329. 
Catlinite,  342. 
Cat's  eye,  136. 
Celestine,  110. 
Cerasite,  268. 
Cereolite,  329. 
Cerine,  207. 
Cerite,  207. 

CERIUM,  ores  of,  206. 
Cerium,  Carbonate  of,  206. 

Phosphate  of,  207 

Silicate  of,  207. 
Cerium  ocher,  206. 
Ceruse,  264,  (White  Lead.) 
Chabazite,  169. 
Chalcedony,  135. 
Chalcolite,"  210. 
Chalk,  116. 

Red,  218. 
Chalybeate  waters,  80. 
Chamoisite,  226. 
Chenocoprolite,  324. 
Chessy  copper,  283,  (Azurite.) 
Chiastolite,  174. 


418 


INDEX. 


Childrenite,  132. 
Chiolite,  132. 
Chlorite,  145. 
Chlorite  slate,  338. 
Chlorite  rock,  338. 
Choritoid,  172. 
Chloropal,  226. 
Chlorophane,  122. 
Chlorophyllite,  162. 
Chlorospinel,  160. 
Chondrodite,  157. 
Christianite,  329. 
Chromate  of  lead,  267. 

of  lead  and  copper,  268. 
Chrome  salts,  manufacture  o/,223. 
Chrome  yellow,  223,  267. 
Chromic  iron,  222. 

ocher,  243. 
CHROMIUM,  243. 
Chrysoberyl,  199. 
Chrysocolla,  283. 
Chrysolite,  156. 

Iron,  226. 
Chrysoprase,  135. 
Cimolite,  162. 
Cinnabar,  270. 
Cinnamon  stone,  185. 
Cipolin  marbles,  349. 
Clausthalite,  263, 
Clay,  352. 

for  bricks,  355. 

for  pottery,  356. 
Clay  slate,  341. 

Clay  Iron  Stone,  218,  220,  228. 
Cleavelandite,  178. 
Clinkstone,  340. 
Clintonite,  148. 
Cloanthite,  244. 
Coal,  mineral,  85. 

Anthracite,  85. 

Bituminous,  85. 

Brown,  86. 

Caking,  85. 

Cannel,  86. 

Cherry,  85. 

Glance,  85. 

Splint,  86. 

Stone,  85. 

Wood,  86. 
Coal  measures,  86. 
COBALT,  247. 
Cobalt,  Arsenate  of,  248. 


Cobalt,  Arsenical,  247. 
Arsenite  of,  249. 
Black  oxyd  of,  248. 
Earthy,  248. 
Red,  249. 
Sulphate  of,  249. 
Sulphuret  of,  248. 
Tin-white,  247. 
White,  247. 
Cobalt  bloom,  248. 

mica,  248,  (cobalt  bloom.) 

ocher,  249. 

pyrites,  248. 

Cobalt  Ores,  gen.  remarks  on,  249. 
Cobaltie  lead  ore,  263. 
Cobaltine,  247. 
Coccolite,  151. 
Colcothar,  214,  227. 
Coiophonhe,  186. 
Coiumbite,  224. 
^omptonite,  167. 
Condurrite,  285. 
Conglomerate,  344. 
Uopal,  Fossil,  97. 
COPPER,  iJ73,  285 
Copper,  Alloys  of,  289. 

Antimonial,  278. 

Arsenates  of,  284. 

Arsenical,  278. 

Carbonates  of,  281,  283. 

Chlorid  of,  285. 

Crenate  of,  285. 

Muriate  of,  285,  (Chlorid) 

Native,  273. 

Oxyds  of,  279. 

Phosphates  of,  285. 

Pyritous,  275. 

Selenid  of,  279. 

Silicate  of,  283,  284. 

Sulphate  of,  280. 

Sulphato-chlorid  of,  285. 

Sulphurets  of,  275. 
Copper  froth,  284. 

mica,  284. 

nickel,  244. 

pyrites,  275,  277. 

uranite,  210. 
Copper  ore,  Black,  279. 

Blue,  275. 

Gray,  278. 

Octahedral, 279  (Red  Copper.) 

Red,  279, 


INDEX. 


419 


Copper  ore,  Variegated,  277. 

Velvet,  285. 

Vitreous,  275. 
Copper  ores,  gen.  remarks  on,  285 

Assay  of,  285. 

Reduction  of,  286. 
Copperas,  227. 

Manufacture  of,  213. 
Coquimbite,  227. 
Coracite,  210. 
Cordierite,  190. 
Cork,  Mountain,  154. 
Corneous  lead,  263. 
Corundum,  158. 
Cotunnite,  268. 
Couzeranite,  179. 
Crichtonite  222, 
Crocidolite,  227. 
Crocoisite,  267. 
Cronstedtite,  226. 
Cross  stone,  174,  (Staurotide.) 
Cryolite,  132. 
Cryptolite,  207. 
Cuban,  277. 
Cube  ore,  230. 
Cube  spar,  114,  (Anhydrite.) 
Cuivre,  French  for  Copper. 
Cummingtonite,  156. 
Cupreous  anglesite,  264. 
Cyanite,  (Kyanite,)  173. 
Cymophane,  200. 
Cyprine,  184. 

D. 

Damourite,  172. 
Danaite,  215. 
Danburite,  329. 
Datholite,  142. 
Davyne,  179,  (Nepheline.) 
Derbyshire  spar,  122. 
Dermatine,  149. 
Deweylite,  145,  (Serpentine.) 
Diallage,  151. 
Diallage  rock,  339. 
Dialiogite,  242. 
Diamond,  80. 
Diaspore,  132. 
Dichroite,  190. 
Digenite,  275. 
Diopside,  150. 
Dioptase,  284. 
Diorite,  339. 
Dioxylite,  266. 


Diphanite,  171 
Dipyre,  181. 
Disthene,  173. 
Dog  tooth  spar,  115. 
Dolerite,  339. 
Dolomite,  118. 
Dreelite,  110. 
Dufrenoysite,  263. 
Dysclasite,  142. 
Dysiuite,  161. 
Dysodile,  97. 

E. 
Earthy  cobalt,  248. 

manganese,  241. 
Edelforsite,  143. 
Edingtonite,  171. 
Edwardsiie,  206,  (Monazite.) 
Egeran,  184. 
Eisen,  German  for  Iron, 
Eiajolite,  180. 
Elastic  bitumen,  94. 
Electric  calamine,253. 
Emerald,  197. 

Oriental,  158. 
Emery,  158. 
Enceladite,  294. 
Epidote,  182. 
Epistilbite,  171. 
Epsom  salt,  124. 

Manufacture  of,  119, 124, 125, 
Eremite,  206,  (Monazite.) 
Erinite,  284. 
Erz,  German  for  ore. 
Esmarkite,  191. 
Essonite,  185. 
Etain,  Fr.  for  tin. 
Eucairite,  323. 
Euchroite,  284. 
Euclase,  199.  m 

Eudialyte,  202. 
Eugenesite,  310. 
Euphotide,  339. 
Eupyrchroite,  120. 
Euxenite,  208. 

F. 

Fahlerz,  278,  (gray  copper.) 
Fahlunite,  163. 
Fassaite,  151. 
Faujasite,  171. 
Feather  alum,  128. 
Feather  ore,  302. 
Feldspar,  176. 


4*20 


INDEX. 


Feldspar,  Glassy,  176,  177. 

Labrador,  178. 
Fer,  French  for  iron. 
Fergusonite,  208. 
Ferrotantalite,  225. 
Fettbol,  162. 
Fibro-ferrite,  227. 
Fibrolite,  172,  (Bucholzite,) 
Fichtelite,  97. 
Figure  stone,  343. 
Flagging  stone,  337,  346. 
Flint,  136. 
Float  stone,  137. 
FlosFerri,  118. 
Flucerine,  206. 
Fluellite,  1-32. 
Fluor  epar,  121. 
Foliated  tellurium,  263. 
Fontainbleau  limestone,  245. 
Forsterite,  157. 
Fossil  copal,  97 

wood,  138,  350. 
Franklinite,  221. 
Freestone,  345. 
Fuchsite,  193. 
Fuller's  earth,  354. 
Fusible  metal,  259. 
G. 

Gadolinite,  208. 
Gahnite,  161,  (Automolite/> 
Galena,  260. 

Galmey,  253,  (Calamine.) 
Garnet,  184. 

Tetrahedral,  187,  (Kelvin. 

White,  175,  (Leucite.) 
Gay  Lussite,  108. 
Gehlenite,  181. 
Genesee  oil,  96. 
German  silvejj,  246. 
Geocronite,  %2. 
Gibbsite,  131. 
Gibraltar  rock,  350. 
Gieseckite,  180. 
Gigantolite,  163. 
Gilbertite,329. 
Girasol,  139. 
Gismondine,  168. 
Glance  cobalt,  247,  (Cobaltine.) 
Glauberite,  108. 
Glauber  salt,  102. 
Glaucolite,  179. 
Glimmer,  Germ,  for  mica. 


Glottalite,  171. 
GLUCINA,  197. 
Gneiss,  337. 
GOLD,  311. 

Gold,  amount  deposited  at   U.  S, 
mint,  315, 

cupellation  of,  317. 
Gong,  Chinese,  290. 
GOthite,  221. 
Gouttes  d'  eau,  195. 
Grammatite,  153. 
Granite,  335. 
Granulite,  335. 
Graphic  gold,  319. 

granite,  335. 

tellurium,  319. 
Graphite,  91. 
Gray  antimony,  301. 

copper  ore,  278. 
Graystone,  339. 
Green  diallage,  151 

earth,  226. 

iron  stone,  230. 

malachite,  281. 

sand,  226. 

vitriol,  227. 
Greenockite,  257. 
Greenovite,  293. 
Greenstone,  339. 
Grengesite,  22C. 
Grit  rock,  344. 
GrOppite,  162. 
Grossularite,  185. 
Guanite,  101. 
Gurhofite,  119. 
Guyaquillite,  97. 
Gypsum,  112. 

Anhydrous,  114. 
Gyrasol,  139. 

H. 

Hematite,  218,  220. 
Haidingerite,  302,  305. 
Hair  salt,  124. 
Halloylite,  160. 
Harmotome,  168. 
Harringtonite,  167. 
Hartite,  97. 
Hatchetine,  97. 
Hauerite,  242. 
Hausrnannite,  242 
Hauyne,  196. 
Haydenite,  170 


I3TDKX. 


421 


Hayesine,  123. 
Heavy  spar,  108. 
Hedenbergite,  151,  226 
Hedyphane,  267. 
Heliotrope,  137. 
Helvin,  200. 
Hematite,  brown,  220. 

Red,  218. 
Hercinile,  161. 
Herrerite,  300, 
Herscheiite,  170. 
Heteroclin,241. 
Heterosite,  242. 
Heulandite,  164. 
Hisingerite,  226. 
Hone  slate,  337,338,342. 
Honey  ttone,  132. 
Hopeite,  254. 
Horn  quicksilver,  271. 

silver,  323. 
Hornblende,  152. 
Hornblende  slate,  337. 
Hornstone,  136. 
Houille,  FT.  for  coal. 
Hudsonite,  151. 
Humboldtilite,  181. 
Humite,  Chondrodite  ?  157. 
Huraulite,  242. 
Hyacinth,  20 1,1 89, 
Hyalite,  140. 

Hyalosiderhe,  156,  (Chrysolite.) 
Hydraulic  limestone,  350. 
Hydroboracite,  123. 
Hydrochloric  acid,  77. 
Hydrogen, 

Carbureted,  77. 

Phosphureted,  77. 

Sulphureted,  77. 
Hydroroagnesite,  125. 
Hydrophane,  139. 
Hydrotalcite,  329. 
Hydrous  anthophyllite,  171. 
Hypersthene,  151. 
Hystatite,  222. 

JL» 

Iberite,  163. 
Ice,  78. 

Ice  spar,  176, 178. 
Iceland  spar,  116. 
Ichthyophthalmite,  165,  (Apophyl- 

lite.) 
Idocrase,  184. 


Idrialin.  97. 
Ilmenite,  222, 
Ilvaite,  226. 
Indicolite,  188". 
lodic  silver,  324. 

mercury,  272. 
lolite,  190. 

Hydrous,  163. 
Indium,  309. 
Iridopmine.  309. 
IRON,  211. 

History  of,  231. 

Manufacture  of,  232,  236 
Iron,  Arsenates  of,  230 

Arsenical,  215, 

Carbonate  of,  228. 

Carburet  of,  91. 

Chromate  of,  222. 

Columbate  of,  224. 

Hemaihic,  218,  220. 

Hydrous  oxyd  of,  220. 

Meteoric,  211. 

Native,  211, 

Oligiste,  218. 

Oxalate  of,  230. 

Oxyds  ofk216,  218,220. 

Phosphate  ofr  229. 

Silicates  of,  226. 

Sparry  or  spathic,  228. 

Specular,  218. 

Sulphate  of,  227. 

Sulphurets  of,  212,  214. 

Titanic,  222. 

Tungstate  of,  225. 
Iron  chrysolite,  226. 
Iron  earth,  Green,  230. 

Blue,  230. 
Iron  furnace,  233. 
Iron  mica,  229,  (Vivianite.) 
Iron  ores,  general  notice  of,  231. 

Assay  of,  232. 

Seduction  of,  232. 
Iron  ore,  Argillaceous,  218,  220 
228. 

Axotomous,  222,  (Ilmenite.) 

Bog,  220. 

Brown,  220. 

Chromic,  222. 

Green,  230. 

Jaspery,  218. 

Lenticular,  218. 

Magnetic,  216. 


36 


422 


INDEX. 


Iirm  ore,  Micaceous,  218. 

Ochreous,  218,  220. 

Octahedral,  216. 

Pitchy,  241,  (Triplite.) 

Red,  218. 

Rhombohedralj  218,   (Specu- 
lar.) 

Spathic,  228. 

Specular,  218. 

Titanic,  222. 
Iron  pyrites,  212. 

Arsenical,  215. 

Auriferous,  213. 

Hepatic,  214. 

Magnetic)  214. 

White,  2 14. 
Iron  sinter,  230. 
Iron  stone,  Clay,  218,  228. 

Blue,  230. 
Iron  zeolite,  227. 
Iserine,  222. 
Isopyre,  226. 
Itacolumite,  343. 
Ixolyte,  97. 

J. 

Jade,  147. 
Jamesonite,  302. 
Jargon,  201. 
Jasper,  137. 
Jaspery  iron  ore,  218. 
JefTersonite,  151. 
Jet,  86. 

Johannite,  210. 
Junkerite,  229. 

K. 

Kakoxene,  230. 
Kaliphite,  330. 
Kalk,  Germ,  for  lime. 
Kamrnererite,  149. 
Kaolin,  177,  356. 
Karpholite,171. 
Karphosiderite,  230. 
Keilhauite,  293. 
Kerolite,  146. 
Kiesel,  Germ,  for  silica. 
Kilbrickenite,  302. 
Kirwanite,  226. 
Knebelite,  226. 
Kobalt,  see  Cobalt. 
Kobellite,  301 
Kollyrite,  162. 
Konigite,  281. 


Konlite,  97 
Kraurite,  230. 
Krisuvigite,28L 
Kupfer,  Germ,  for  copper. 
Kyanite,173> 

L. 

Labradorite,  178. 
Labrador  feldspar,  178. 

hornblende,  151. 
Lapis  Lazuli,  196. 
Latrobite,  179. 
Laumonite,  166, 
Lava,  340. 
Lazulite,  131. 
LEAD,  259. 
Lead,  Arsenate  of,  267. 

Arsenids  cf,263. 

Carbonate  of,  264. 

Chlorid  of,  268. 

Chromate  of,  267. 

Molybdate  of,  268. 

Muriate  of,  268. 

Native,  260. 

Oxyd  of,  263. 

Phosphate  of,  266. 

Selenate  of,  268. 

Selenids  of,  263. 

Sulphate  of,  264. 

Sulphato-carbonates  of,  266. 

Sulphuret  of,  260. 

Telluridsof,  263. 

Tungstate  of,  268. 

Vanadate  of,  268. 
Lead  glance,  260,  (Galena.) 
Leadhillite,  266. 
Lead  ore,  Argentiferous,  260. 

Cobaltic,  263. 

Red,  263. 

White,  264. 

Yellow,  268,  (Molybdate.) 
Lead    ores,  general   remarks   on, 

268. 

Ledererite,  169. 
Lederite,  293. 
Leonhardite,  166. 
Lepidokrokite,  221. 
Lepidolite,  192. 
Lepidomelane,  193. 
Leptynite,  335. 
Leucite,  175. 
Leucophane,  200. 
Leucopyrite,  216. 


423 


Levyne,  169. 
Libfthenite,  285. 
Liebigite,  330. 
Lievrit*1, 226. 
Lignite,  86. 
Ligurite,  330. 
LIME,  112, 141. 
Lime,  Arsenate  of,  305. 

Borate  «f,  123. 

Borosilicate  of,  142. 

Carbonate  of,  115,118. 

Fluate  of,  121. 

Fluorid  of,  121. 

Magnesian  carbonate  of,  118. 

Nitrate  of,  123. 

Oxalate  of,  123. 

Phosphate  of,  120. 

Silicates  of,  141,  142. 

Sulphate  of,  112,  114. 

Tungstate  of,  300. 

Vanadate  of,  300. 
Limestone,  116,347. 

Hydraulic,  117,  350. 

Magnesian,  118. 

Fontainebleau,  116. 
Limestone,  burning  of,  351. 
Limekilns,  351. 

Limonite,  220,  (Brown  Hematite.) 
Lincolnite,  164. 
Liroconite,  284. 
Lithia  mica,  192. 
L  t'lographic  stone,  10. 
Lithomarge,  355. 
Liver  ore  of  mercury,  271. 
Lodestone,  217. 
Loxoclase,  178. 
Lumachelle,  350. 
Lydian  stone,  137. 
M. 

Made,  174. 

Maclurite,  157,  (Chondrodite.) 
MAGNESIA,  123,  143. 
Magnesia,  Borate  of,  126. 

Carbonate  of,  124,  125. 

Fluopho-phate  of,  127. 

Fluosilicate  of,  157,  (Chondro- 
dite.) 

Hydrate  of,  126. 

Hydro-carbonate  of,  125. 

Native,  126,  (Brucite.) 

Nitrate  of,  126. 

Silicates  of,  143. 


Magnesia,  Sulphate  of,  124. 
Magnesia  alum,  128. 
Vlagnetsian  limestone,  118. 
Magnesite,  124. 
Magnet,  Native,  217. 
Magnetic  iron  ore,  216. 

pyrites,  214. 
Malachite,  Blue,  283,  (Azuritc.) 

Green,  281. 
Malacolite,  150. 
Malacone,  202. 
Maltha,  95. 
Maltha  cite,  162. 
Mancinite,  254. 
Manganblende,  242. 
MANGANESE,  239. 
Manganese,  Arseniuret  of,  242. 
Bog  or  earthy,  241. 
Carbonate  of,  242. 
Oxyds  of,  240,242. 
Phosphate  of,  241. 
Silicate  of,  239. 
Sulphuret  of,  242. 
Manganese  ores,  general  remark* 

on,  242. 

Manganese  spar,  239. 
Manganite,  242. 
Marble,  347,  348,  349, 350. 

Marcasite,  212,  (Pyrites.) 
Marceline,  241. 

Marekanite,  341. 

Margarite,  193. 

Margarodite,  193. 

Marl,  354. 

Marmatite,  250,   Blende.) 

Mannolite,146. 

Martinsite,  107. 

Mascagnine,  101. 

Ma.-onite,  172. 

Medjidite,  330. 

Meerschaum,  148. 

Meionite,  181. 

Melanchlor,  230. 

Melanite,  185. 

Melanochroite,  267. 

Mellate  of  alumine,  132, 

Mellilite,  181. 

Mellite,  132. 

Menaccanite,  222, 

Menilite,  140. 

MERCURY,  270. 

Mercury,  Chlorid  of,  371. 


431 


Mercury,  lodic,  272. 

Muriate  of,  271,  (Chlorid.) 

Native,  270. 

Selenid  of;  272. 

Sulpfeuret  of,  270. 
Mercury  ores,  general  remarks  on, 

272. 

Mesitine  spar,  229. 
Mesole,  167. 
Mesatype,  167. 
METALS,  202. 
Meteoric  iron,  211. 
Miargyrite,  323. 
Mica,  191. 

Hydrous,  193. 
Mica  slate,  337. 
Micaceous  iron  ore,  218. 
Microiite,  208. 
Middletonite,  97. 
Miemite,  119. 
Millstone  grit,  344, 
Miloschine,  243. 
Mimetene,  267. 
Mineral  caoutchouc,  94. 

oil,  95. 

pitch,  95. 

tallow,  97. 

tar,  95. 

waters,  80. 
Minium,  263. 
Mispickel,  215. 
Mocha  stone,  135. 
Molybdate  of  lead,  268. 
Molybdenum,  Sulphuret  of,  298. 
Molybdenite,  298. 
MOLYBDENUM,  298. 
Molybdic  ocher,  299. 
Monazite,  206. 
Monradite,  149. 
Monticeliite,  330. 
Moonstone,  176. 
Moroxite,  120. 
Mosaic  gold,  259. 
Mosandrite, 

Mountain  green,  281,  (Green  Mal- 
achite.) 

cork,  154. 

leather,  154. 
Mowenite,  167. 
Mailer's  glass,  140. 
Mullicite,  230. 
Mundic.  214. 


Muriacite,  114, 
Muriatic  acid,  77, 
Murchisonite,  176,  (Feldspar.) 
Muscovy  glass,  192. 

N. 

Nacrite,  193. 
Naphtha,  95. 
Natrolite,  166. 
Natron,  103. 
Necronite,  177. 

Needle  ore,  258  ( Acicukr  Bismuth.) 
Needlestone,  167,  (Scokcite.) 
Nemalite,  125. 
Nepheline,  179, 
Nephrite,  147. 
NICKEL,  243. 
Nickel,  Antimonial,  244. 

Alloys  of,  246. 

Arsenate  of,  245. 

Arsenical,  244. 

Bismuth,  245. 

Copper,  244. 

Oxydof,245. 

White,  244. 
Nickel  glance,  244. 

green,  245. 

ocher,  245. 

pyrites,  245. 

stibine,  244. 
Nickel  ores,  general  remarks  on, 

245. 

Nigrine,  291. 
Nitrate  of  lime,  123. 

magnesia,  126. 

potash,  101. 

soda,  103. 
Niter,  101. 
Nitrogen,  76. 
Nontronite,  226. 
Nosean,  196. 
Novaculite,  342. 
Nussierite,  330. 
Nuttallite,  181. 

O. 

Obsidian,  341. 
Ocher,  Red,  218. 

Brown  or  yellow,  220. 

Cerium,  206. 

Plumbic,  263. 

Uranic,  209. 

Chromic,  243. 
Octahedrite,  292,  (Anatase.) 


INDEX. 


425 


(Erstedite,  202. 

Oil,  Gent- see  or  Seneca,  96. 

Mineral,  95. 
Okenite   142. 
Oligiste  iron  ore,  218. 
Oligoclase,179. 
Oligou  spar,  229. 
Olivenite,  284. 
Olivine,  156. 
Onyx,  136. 
Oolite,  116. 
Opal,  139. 

Ophite,  145,  (Serpentine.) 
Ores,  general  remarks  on,  202. 
Orpiment,  305. 
Orthite,207. 

Orthoklase,  176,  (Feldspar.) 
Ottrelite,  193. 
Ouvarovite,  185. 
Oxalate  of  iron,  230. 
Ozarkite,  330. 
Ozocerite,  97. 
Packfong,  246. 
PALLADIUM,  310. 
Pargasite,  154. 
Parisite,  206. 
Peastone,  116,  (Pisolite.) 
Pearl  spar,  119. 
Pearlstone,  341. 
Pectolite,  142. 
Peloconite,  242. 
Pennine,  149. 
Periclase,  149. 
Peridot,  156,  (Chrysolite.) 
Perovskite,  293. 
Petalite,  182. 
Petroleum,  95. 
Phacolite,  170. 
Pharmacolite,  305. 
Phenacite,  200. 
Phillipsite,  168. 
Pholerite,  162. 
Phonolite,  340. 
Phosphorite,  120. 
Phosphureted  hydrogen,  77. 
Photozite,  239. 
Phyllite,  193. 
Physalite,  194. 
Piauzite,  97. 
Pickeringite,  129. 
Picrolite,  146. 
Picrophyil,  331. 


Picrosmine,  149. 

Pigotite,  330. 

Pimelite,  245. 

Pinchbeck,  290. 

Pinguite,  226. 

Finite,  162, 

Pipe  clay,  356. 

Pipestone,  342. 

Pisolite,  116. 

Pistacite,  183. 

Pitchblende,  209. 

Pitchstone,  341. 

Pitchy  iron  ore,  241,  (Triplite.) 

Pittizite,  227. 

Placodine,  244. 

Plagionite,  302. 

Plasma,  136. 

Plaster  of  Paris,  114. 

Platin-iridium,  309. 

PLATINUM,  307. 

Pleonaste,  160. 

Plumbago,  91. 

Plumbic  ocher,  263. 

Plumbo-calcite,  117.  < 

Plumbo-resinite,  268. 
Pollux,  330. 
Polybasite,  323. 
Polycrase,  209. 
Polyhalite,  127. 
Polyhydrite,  226. 
Polylite,151. 
Polymignite,  209. 
Poanahlite,  167. 
Porcelain,  manufacture  of,  356. 
Porcelain  clay,  356. 
Porcelain  jasper,  137. 
Porcelain  spar,  330. 
Porphyry,  340. 
Porphyritic  granite,  335. 
Potash,  Nitrate  of,  101. 
Potash,  Salts  of,  101. 
Potassium,  Chlorid  of,  102. 
Potstone,  143, 339. 
Potter's  clay,  356. 
Pottery,  manufacture  of,  356. 
Pozzuolana,  347,  351. 
Prase,  134. 
Praseolite,  330. 
Prehnite,  170. 
Proustite,  323,  (Red  silver.) 
Pseudomalachite,  285. 
Pseudomorphs,  Steatitic,  149. 
36* 


426 


INDEX. 


Pudding  stone,  344. 

Pumice,  341. 

Purple  or  variegated  copper,  277. 

Pycnite,  194. 

Pyrenaite,  185. 

Pyrites,  Arsenical  iron,  215. 

Auriferous,  213. 

Capillary,  245. 

Cockscomb,  214. 

Copper,  275. 

Hepatic,  214. 

Iron,  212. 

Magnetic,  214. 

Nickel,  245. 

Radiated,  214. 

Spear,  214.      •  -  ' 

Tin,  294. 

Variegated  copper,  277. 

White  iron,  214. 
Pyrochlore,  208. 

Pyrodmalite,  227,  (Pyrosmalite.) 
Pyrolusite,  240. 
Pyromorphite,  266. 
Pyrope,  187. 
Pyrophillite,  149. 
Pyrophysalite,  194. 
Pyrorthite,  207. 
Pyrosclerite,  149. 
Pyrosmalite,  227. 
Pyroxene,  150. 
Pyrrhite,  293. 

Q. 
Quartz,  132. 

Amethystine,  134. 

Aventurine,  134. 

Ferruginous,  135. 

Granular,  137,  343. 

Greasy,  134. 

Milky,  134. 

Rose,  134. 

Smoky,  134. 

Tabular,  137. 
Quartz  rock,  343. 
Quicklime,  117,350. 
Quicksilver,  270. 

Chlorid  of,  271. 

Horn,  271. 
Quincite,  148. 
Realgar,  305. 
Red  antimony,  303. 

chalk,  218. 

cobalt,  249. 


Red  copper  ore,  279. 

hematite,  218, 

iron  ore,  218. 

lead,  263. 

silver  ore,  323. 

zinc  ore,  251. 
Reddle,  218,  (Red  chalk.) 
Rensselaerite,  144,  149. 
Retinalite,  149. 
Retinasphalt,  95. 
Reunite,  95. 
Rhffitizite,  173. 
Rhodium  gold,  311. 
Rhodizite,  127. 
Rhodonite,  239. 
Rhomb  spar,  119,229. 
Ripidolite,  145. 
Rock  or  mountain  cork,  154. 

crystal,  133. 

milk,  116. 

salt,  104. 

soap,  162. 

ROCKS,    general    remarks   on, 
332. 

Expansion  of,  334. 
Romeine,  303. 
Roofing  slate,  341. 
Rose  quartz,  134. 
Roselite,  249. 
Rosite,  162. 
Rubellite,  188. 
Rubicelle,  160. 
Ruby,  Spinel,  160. 

Almandine,  160. 

Balas,  160. 

Oriental,  158. 
Ruby  silver  ore,  323. 
Rutile,  291. 
Ryacolite,  178. 

S. 

Saccharite,  175. 
Sahlite,  150. 
Sal  ammoniac,  100. 
Saline  springs,  106. 
Salt,  Common,  104. 

Epsom,  124. 

Glauber,  102. 
Saltpeter,  101. 
Samarskite,  210. 
Sand,  352. 

for  glass,  353. 

for  casting,  354. 


INDEX, 


42* 


Sandstone,  344. 

Flexible,  343. 
Saponite,  145. 
Sappar,  173. 
Sapphire,  158, 
Sarcolite,  168,(Analcime.y 
Sard,  135. 
Sardonyx,  135, 
Sassolin,  107. 
Satin  spar,  113,  116, 
Saussurite,  330. 
Scapolite,  180. 
Scheelite,  300,  (Tangsten.) 
Scheereritfi,  97. 
Schiller  asbestus,  146, 

spar,  148. 
Schist,  341. 
Schorl,  188. 
Schorlomite,  209. 
SchrOtterite,  162. 
Schwefel,  Germ,  for  sulphur. 
Scolecite,  167. 
Scoria,  341. 
Scorodite,  230. 
Scythe  stones,  337,338, 
Sea  froth,  148. 
Sea  water,  79. 

Dead,  79. 

Selenate  of  lead,  268, 
Selenite,  113. 
Selenpalladite,  310. 
Selenid  of  copper,  279. 

of  lead,  263. 

of  mercury,  272, 

of  silver,  323. 
Selensilver,  323. 
Semiopal,  139. 
Seneca  oil,  96. 
Serbian,  243. 
Serpentine,  145, 339. 
Seybertite,  149. 
Shale,  341. 
Sicilian  oil,  96. 
Sideroschisolite,  226. 
Sienite,  335. 
SILICA,  132. 
Siliceous  sinter,  140. 
Silicified  wood,  138. 
Sillimanite,  172. 
SILVER,  319. 
Silver,  Antimonial,  323. 

Antimouial  sulphuret,  322, 332. 


Silver  Bismnthic,  319. 

Bromic,  324. 

Carbonate  of,  323. 

Chlorid  of,  323. 

Horn,  323. 

lodic,  324. 

Muriate  of, 

Native,  319. 

Red  or  ruby,  323. 

Selenids  of,  323. 

Sulphured  of,  321, 322. 

TeHuric,  323. 
Silver  ore,  Black,  322. 

Brittle,  322. 

Red  or  ruby,  323. 

Vitreous,  321. 

Silver  ores,  general  remarks 
324, 

Seduction  of,  326. 
Sinter,  Siliceous,  140. 

iron,  230. 

Skapolith,  180,  (Scapolite.) 
Skolecite,  167. 
Skorodite,  230. 
Slate,  337,  338,  341, 
Smalt,  250. 
Smaltine,  247. 
Smelite,  162. 
Soda,  Salts  of,  102. 

Carbonate  of,  103. 

Nitrate  of,  103. 

Sulphate  of  102,  108. 
Sodalite,  197. 
Soapstone,  143,  338. 
Sodium,  Chlorid  of,  104. 
Somervillite,  181. 
Spadaite,  149. 
Spar,  Calcareous,  115. 

Derbyshire,  122. 

Heavy,  108, 

Tabular,  141. 

Sparry  or  spathic  iron,  223. 
Spear  pyrites,  214. 
Specular  iron,  218. 
Speculum  metal,  290. 
Speiss,  245. 
Sphene,  292. 
Spherosiderite,  228. 
Spherulite,  341. 
Spinel,  160. 
Spinel  ruby,  160. 
Spinel,  zinciferous,  161. 


42B 


INDEX, 


Spinellane,  196, 
Spodumene,  181, 
Stalactite,  116. 
Stalagmite,  116. 
Staurotide,  174. 
Steatite,  143,  338. 
Steatitic  pseudomorphsr 
Steinmannite,  302. 
Stellite,  142,171. 
Sternbergite,  322. 
Stiblite,  303. 
Stilbite,  165. 
Stilpnomelane,  226. 
Stilpnosiderite,  221, 
Stinkstone,  117. 
Stroganowite,  330v 
Stromeyerite,  322. 
STRONTIA,  110, 
Strontia,  Carbonate  of,  111, 

Sulphate  of,  110, 
Strontianite,  111. 
Struvite,  101. 
Sulphur,  97,  98, 
Sulphuric  acid,  99. 
Sulphurous  acid,  99, 
Sulphureted  hydrogen,  77. 
Sunstone,  176. 
Syenite,  335. 
Symplesite,  230. 

Ti 

Tabasheer,  140. 
Tabular  spar,  141. 

quartz,  137. 
Tachylite,  330. 
Talc,  143. 
Talcose  slate,  338. 

rock,  338. 

Tallow,  Mineral,  97, 
Tantalite,  224. 
Tautolite,  330. 
Telluric  Silver,  323. 

Bismuth,  258. 

Lead,  263. 
TELLURIUM,  300. 
Tellurium  ores,  300,  319. 
Tennantite,  279. 
Tenorite,  279, 
Tephroite,  240. 
Tesselite,  165,  (Apophyllile.) 
Tetradymite,  258. 
Thenardite,  108. 
Thomaite,  229- 


Thomsonite,  167, 
Thorite,  202. 
Thrombolite,  285-, 
Thulite,  183. 
Thumite,  190, 
Thuringite,  226. 
Tile  ore,  279. 
TIN,  294. 
Tin,  Alloys  of,  297,  2901 

Native,  294. 

Oxyd  of,  295 

Stream,  295. 

Sutphuret  of,  294. 

Wood,  295. 
Tin  ore,  295, 
Tin    ores,    general    remarks   ett^ 

296. 

Tin  pyrites,  294. 
Tincal,  107. 
Titanic  acid,  291,  29S. 

iron,  222, 
Titanite,  292. 
TITANIUM,  290. 
Titanium  ores,  291,  292, 293> 
Toadstone,339. 
Topaz,  194. 

False,  134. 

Oriental,  158v 
Topazolite,  185. 
Touchstone,  137. 
Tourmaline,  187. 
Trachyte,  340. 
Trap,  339. 
Tremolite,  153. 
Triphane,  182. 
Triphyline,  230. 
Triplite,  241. 
Tripoli,  354. 
Trona,  103. 
Troostite,  240. 
Tschevkinite,  209. 
Tuesite,  355. 
Tufa,  347. 

Calcareous,  116. 
Tungstate  of  iron,  225. 

lead,  268. 

lime,  300. 

TUNGSTEN,  299, 
Tungsten,  Calcareous,  300. 

Ferruginous,  225,  (Wolfram.) 
Tungstic  ocher,  299 
Turgite,  221. 


Tarqaore,  130. 
Type  metal,  504. 

U. 

Ultramarine,  196. 

Uranite,  210. 

Uran-mica,  210,  (Uraaate.) 

(Uraniain  ores,  209. 

Uran  ocher,  209. 

Uranium,  Phosphate  of,  21H. 

Oxyd  of,  209. 

Sujphate  of,  2 10 
Uranium  ore,  Pitchy,  289. 
tJrano-tantalhe,  21®. 
Uran-vitriol,  210. 
Urao,  103,  (Trona.) 

V. 

Vanadate  of  lead,  268. 
oflirae,300. 
of  copper,  285, 
Vanadinhe,  268. 
VANADIUM,  300. 
Variegated  copper  ore,  277. 
Vauquelinite,  268. 
Velvet  copper  ore,  285. 
Verd  aRtique,  146. 

<memal,  340, 
Verraiculite,  149. 
Vet-million,  271. 
Vesuvian,  184. 
Villarsite,  149, 
Vitreou&copper  «re,  275. 

silver  ore,  321. 
Vitriol,  Blue,  280. 

Cobalt,  249. 

Green,  227. 

Red,  336. 

Wkite,  252. 
Vivianite,  229. 
Volcanic  ashes,  341. 

glass,  341. 

scoria,  341. 
Voltaite,  228. 
Voltzite,  252. 
Vulpinite,  114. 


W. 


Wacke,  339. 
Wad,  241. 
Wagnerite,  127- 


Vft9hiHgtonite,222. 
Varwickite,  293. 
Vater,  78. 

Mineral,  80. 

Sea,  79. 

Dead  sea,  79. 
Vavellite,  130. 
Vebsterite,  129. 
iVeissite,  182. 
iVeraeiate,  181. 
Vhetstone,  342,  34S. 
antimony,  30S. 

arsenic,  305. 

iron  pyrites,  214. 

lead  ere,  264. 

tellurium,    313,     (AuroteU*- 
rke.) 

vitriol,  252. 
Vichtine,  182. 
Vilkmite,  254. 

Yismuth,  German  for  Bismuth. 
Vithamite,  182,  (Epidote.) 
Witherile,  109. 
Ycertliite,  173. 
Wohlerite,  202. 
Wolchonfikoite,  243. 
Wolfram,  225. 

Wollastonite,  141,  (Tabular  spar,) 
Wood,  silicified,  138. 
Wood  opal,  140. 
Wood  tin,  295. 

X. 

Xanthite,  184. 
Xanthophyflite,  148. 
Xenotime,  208. 
Xylite,226. 


Yenite,  2f6. 

Yttria,  Phosphate  of,  208. 

Columbate  of,  2G8. 
Yttrium  ores,  206,  208. 
Yttro-cerite,  206. 
Yttro-columbite,  or  yttro-tantalifcs, 

208. 

Yttre-ilmenite,  210. 
Yttro-titanhe,  293. 


JZaffre,  249. 


Zeagomte,  168; 
Zeolites,  163. 

Iron,  227. 
Zeuxite,.  172. 
ZINC,  250. 
Zinc,  alloys  of,  256,  257. 

Carbonate  of,  253. 

Red  oxyd  of,  251. 

Silicate  of,  253. 

Sulphate  of,  252v 


Zinc,  Sulphuret  ofr  2501 

Zinc  blende,  250. 

Zinc  bloom,  253. 

Zinc  ores,generalremarksan, 

Reduction  of,  25S, 
Zinkenite,  302. 
ZIRCONIA,  200. 
Zircon,  200. 
Zirconite,  201. 
Zoisitev  183, 


APPENDIX   TO   SECOND   EDITION. 


Gold  of  California. — The  gold  region  of  Upper  California  extends 
along  the  valley  of  the  Sacramento^  and  alsa  as  reported,  the  valley  o£ 
San  Joaquin,  immediately  south.  These  two  valleys  constitute,  in  fact, 
a  single  north  and  south  depression  of  the  country,  lying  between  the  lofty 
Sierra  Nevada  on  the  east,  and  the  Coast  Range  on  the- west,  and  having 
a  total  length  of  600  miles.  The  two  rivers  meet  about  midway  in  this 
long  trough,  and  cutting  through  the  Coast  hills,  open  into  the  large  bay 
of  Francisco.  Both  streams  are  bordered  by  extensive  alluvial  flat^,— 
those  of  the  Sacramento  varying  in  breadth  from  15  to,  60  or  80  miles. 
These  alluvial  flats  are  at  two  levels,  differing  60  feet  in  height ;. — the- 
lower,  or  "  bottomland  "  of  the  river  is  a  vast  plain  of  productive  soil ;  the 
upper  has  often  a  pebbly  surface,  and  in  many  parts  is  much  cut  up  by  ra- 
vines, or  reduced*  to  a  collection  of  hills. 

The  tributaries  of  this  large  river  come  mostly  from  the  snowy  heights 
ef  the  lofty  Sierra  on  the  east,  and  the  gold  has  been  found  principally 
along  these  streams.-  Sutler's  settlement  is  situated  near  the  junction 
of  the  Sacramento  and  the'  Ain-eri can  Fork,  about  90  miles  from  the  sea^ 
Oil  this  American  Fork,  gold  was  first  found  early  in  the  Spriag  of 
1848.  Not  only  the  main  stream,  but  its  various  branches,  and  the 
many  ravines  opening  t&wards  it,  have  been  found  to  yield  an  abundant 
return  by  washing  the  sand  or  gravel  of  their  beds,  feather  River 
empties  into  the  Sacramento,  18  or  20  miles  north  of  the  American  Fork. 
This  is  a  large  stream,  with  many  affluents  of  considerable  size,  as 
Yubah,  and  Bear  Rivers  ;  and  here  also  the  gokl  washings  have  beeit 
highly  productive.  Other  branches  of  the  Sacramento  aie  said  to  afford 
gold  with  the  same  ease  and  abundsance. 

The  rudest  mode  of  "panning"  is  at  present  ail  that  is  necessary  to. 
obtain  the  gold.  After  this  process  fails  of  being  pr&fitable,  the  sands 
may  again  be  worked  by  amalgamation,  and  they  must  remain  a  last- 
ing source  of  the  metal.  The  gold'  occurs  in  flattened  grains,  or  scales* 
and  occasionally  in  lumps  of  large  sire.  The  yield  is  enormous  ^  biit 
the  monthly  amount  can  noi  at  present  be  safely  stated. 


APPENDIX.  431 

Tte  author  was  through  this  region  in  1841,  having  traveled  by  land 
from  Oregon  to  Francisco,  and  in  his  course,  followed  down  the  Sacra- 
mento from  one  of  its  sources  just  west  of  Shasty  Peak.  Along  the 
tiead  waters  in  the  Shasty  Mountains,  talcose  rocks  and  slates  were 
€iict  with,  having  the  characters  described  on  pages  316,  338  ;  and  af- 
terwards along  the  valley  of  the  Sacramento,  to  the  west  as  well  as  east, 
the  pebbles  indicated  a  continuation  south  of  the  same  rock  formation. 
The  resemblance  to  other  gold  regions  was  observed  and  remarked  in 
«is  Report.  His  route  led  him  near  the  banks  of  the  Sacramento,  and 
consequently  at  a  distance  from  the  places  where  gold  has  actually  been 
found.  The  same  rocks  were  also  traversed  farther  north,  between  the 
Umpqua  and  Shasty  rivers,  within  30  miles  of  the  sea. 

The  gold  will  undoubtedly  be  detected  in  the  rocks  alluded  to.  Bat 
in  the  Urals,  (p.  312,)  and  nearly  all  gold  regions,  alluvial  washings 
have  been  the  great  source  of  the  precious  metal.  The  sands  and  gravel 
ore  only  the  rocks  broken  ftp  or  pulverized  by  the  action  of  the.elements, 
and  through  abrasion  by  water,  daring  past  ages  ;  and  by  the  rills,  rivulets 
and  streams,  the?e  sands  have  undergone,  in  part,  the  process  of  wash- 
ing, and  hence  the  grains  of  gold  occur  most  abundantly  along  the  bot- 
tom of  the  ravines,  or  the  beds  of  runs  of  water.  The  gold  being  spe- 
cifically about  seven  times  heavier  than  the  gravel,  it  is  left  behind  while 
Ihe  earth  is  carried  off.  Every  winter's  rains  renew  the  process  of 
washing,  and  prepare  the  ground  for  farther  mining.  The  forms  of 
the  grains  of  gold  arise  tote  great  extent  from  the  forms  in  the  rocks, 
and  partly  from  that  wear  which  grinds  up  the  laminae  into  scales,  and 
makes  smooth  the  lumps. 

The  distinctive  characters  of  gold  are  mentioned  on  page  311.  It 
may  be  remarked  farther,  that  nitric  acid  is  also  an  important  test. 
Gold  is  not  acted  upon  at  all  by  strong  or  dilute  nitric  acid,  while  all 
the  baser  metals  cause  an  effervescence,  (with  heat,  if  not  without,)  and 
liberate  acrid  fumes.  If  a  quantity  of  metallic  grains  are  thrown  into 
dilute  nitric  acid,  and  heat  applied,  the  action  will  at  once  distinguish 
the  gold  from  any  metallic  impurity.  Nitro-muriatic  aeid,  (a  mixture' 
of  equal  parts  of  nitric  and  muriatic,)  when  heated  on  gold,  produces  a 
complete  solution,  attended  with  the  escape  offunvs. 

The  metal  platinum  is  also  unacted  upon  by  the  simple  acids,  and 
dissolves  in  nitro-muriatic.  But  the  scales  of  this  metal  have  a  higher 
specific  gravity  than  gold,  and  the  color  is  a  pale  steel  shade. 

In  amalgamation,  the  sand  and  gravel,  after  previous  washing,  are 
agitated  together  in  a  large  vessel  like  a  bowl.  For  reducing  the 
amalgam,  it  is  convenient  to  have  an  iron  crucible  that  will  hold  a 
pint,  to  which  there  is  a  cover  that  may  be  secured  firmly  by  an  iron 
bar  and  a  thumb  screw.  From  the  top  of  this  crucible,  a  bent  tube  may 
lead  out,  having  a  half  inch  bore,  and  one  or  two  feet  long.  The  amal- 
gam—after pressing  it  in  buckskin,  close  nankeen,  or  some  similar  ma- 
terial, to  separate  the  excess  of  mercury  and  reduce  it  to  a  dry  ball,— 
is  placed  in  the  crucible,  the  cover  fitted  on,  and  heat  applied  :  the  mer- 
cury at  a  temperature  of  660°  F.  is  thus  driven  off,  and  the  end  of  the 
tube  being  inserted  into  a  vessel  of  water,  it  is  distilled  over  and  con 
densed  in  the  water.  An  India  rubber  bag,  attached  to  the  end  ot  the 
tube  has  been  recently  brought  into  use  for  collecting  the  mere 
the  ha*,  during  the  distillation,  is  kept  cold  in  water.  By  this  means, 


432  XPPENDTX. 

the  danger  of  the  water's  flowing  up  the  tube  into  the  crucible  is  avoicfecf. 
On  opening  the  retort,  the  gold  is  found  to  have  a  bright  yellow  color,, 
vet  is  light  and  spongy.  It  may  then  be  put  into  a  erueible  and  melted 
with  a  little  borax  or  potash  ;  or  if  impure,  a  little  niter  (salt  peter)  i* 
ndded.  When  fused,  it  is  cast  into  an  ingot,  and  the  work  is  complete, 
\.t  the  Carolina  mines,  about  1000  dwts.  are  thus  produced  at  a  single 
usion. 

In  the  working  of  gold  rocks,  the  rock,  after  mining,  is  stamped  in? 
leavy  stamping  mills,  and  thus  reduced  to  powder.  After  this,  it  is 
.vashed  and  amalgamated  according  to  the  method  stated,  but  with 
some  variations  for  large  works. 

It  has  been  found  profitable,  when  metallic  walpfourets  and  other  ores* 
are  abundant  in  the  rocks,  to  work  the  ores  by  smelting,  as  they  con- 
tain much  gold  that  is  not  collected  by  amalgamation.  It  is  stated 
that  according  to  a  trial  in  Russia,- a  given*  quantity  of  ore,  which  by 
the  ordinary  treatment  yielded  only  five  sixths  of  an  ounce f  produced 
by  the  smelting  process  72  5-6ths  ounces/  o*  n«  kss  than  87  times 
more  than  that  by  the  oM  method. 

The  total  amount  of  gold  received  from  California  at  the  United? 
States  mints  at  Philadelphia  and  New  Orleans,  up  to  the  dose  of  July 
1850,  is  20,934,310  dollars.  The  amount  estimated  at  San  Francisca 
to  have  been  exported  from  California  to  July  1,  is  23  millions  of  dol- 
lars. The  amount  received  at.  the  mint  for  the  6  months  ending  with 
July,  was  at  the  rate  of  26  million?  of  dollars  a  year,  and  for  the  latter 
half  of  that  period,  at  the  rate  of  32  millions  of  dollars  a  year. 

Mines  of  Mercury. — The  Cinnabar  mines  recently  discovered  occur 
In  a  ridge  of  the  Sierra  Azul,  south  of  St.  Joseph,  a  few  siiles  from  the 
coast,  about  half  way  from  San  Francisco  to  Monterey.  The  mouth 
of  the  principal  mine  (the  mine  of  New  Almaden)  is  a  few  yards  down 
from  the  summit  of  the  highest  hill  containing  the  ore,  and  is  about 
1200  feet  above  the  neighboring  plain.  The  prevailing  rock  is  a  green- 
ish talcose  rock.  The  ore  is  interspersed  through  a  yellow  ochreous 
matrix,  which  forms  a  bed  42  feet  in  thickness.  The  richest  ore  is 
from  the  upper  part  of  the  bed. 

Specimens  of  this  ore,  Bent  to  New  Haven  by  Rev.  C.  S.  Lyman,  and 
Been  by  the  author,  are  extremely  rich,  and  indicate  that  it  must  be  ex- 
ceedingly abundant,  as  well  a&  of  unsurpassed  value. 


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